Quadrilateral $abcd$ is a trapezoid with $ab$ parallel to $cd$. we know $ab = 20$ and $cd = 12$. what is the ratio of the area of triangle $acb$ to the area of the trapezoid $abcd$? express your answer as a common fraction.

Answers

Answer 1
Draw a diagram to illustrate the problem as shown below.

The area of triangle acb is
A₁ = (1/2)*20*h = 10h

The area of trapezoid abcd is
A₂ = (1/2)*(20+12)*h = 16h

The ratio A₁/A₂ is
A₁/A₂ = (10h)/(16) = 5/8

Answer:
The ratio of triangle acb to the area of trapezoid abcd is 5/8.
Quadrilateral $abcd$ Is A Trapezoid With $ab$ Parallel To $cd$. We Know $ab = 20$ And $cd = 12$. What

Related Questions

Which is a description of the graph that would represent the inequality below?
12 – 2x < 16

Answers

The graph of the inequality 12 - 2x < 16 is represented by an open circle at -2 on a number line, with shading to the right, indicating all values greater than -2.

To describe the graph representing the inequality 12 - 2x < 16, we first need to solve for x. Subtracting 12 from both sides of the inequality, we get -2x < 4. Dividing both sides by -2 (and remembering to flip the inequality symbol when dividing by a negative), we have x > -2.

Graphically, this is represented on a number line with an open circle at -2 and a shaded area to the right of -2, indicating that x can be any number greater than -2.

Round 846 to the nearest hundred___________ and 3756 to the nearest thousand ________

Answers

846 rounds to 800, and 3756 rounds to 4000.

Which point is a solution of x + 2y ≤ 4?
A. (2,4)
B. (1,1)
C. (3,5)
D. (-1,5)

Answers

B. (1,1), That's the only answer that is actually in the shaded part of the graph. The other points are off and on the other side of the line.

what must be done to the expression x + 108 to make it equal x?

Answers

minus 108 or add -108
Final answer:

To make the expression x + 108 equal to x, subtract 108 from both sides of the equation.

Explanation:

To make the expression x + 108 equal to x, we need to subtract 108 from both sides of the equation. This will give us:

x + 108 - 108 = x - 108

Simplifying the equation, we get:

x = x - 108

However, if we are not solving an equation and simply need to simplify the expression x + 108 to make it equal to x, then the answer is that nothing can be done. The expression cannot be simplified to make it equal to x without additional information or context.

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What does "a"equal to?

Answers

Distribute on the left side
7.4a+22.2=3.2a+43.2
Subtract 3.2a from both sides
4.2a+22.2=43.2
Subtract 22.2 from both sides
4.2a=21
Divide both sides by 4.2
a=5

What is the length of the diagonal of a cube with a side length of 5 cm? Round to the nearest tenth. 7.1 cm 8.7 cm 21.3 cm 26.7 cm

Answers

Diagonal of a cube formula: D=a√3  [a=side length]

D = 5√3 ≈ 8.7 cm.

The required length of the diagonal of a cube with a side length of 5 cm is approximately 8.7 cm.

What is diagonal?

A diagonal is a straight line that connects two non-adjacent corners of a polygon, such as a square, rectangle, or any other shape with four or more sides. For a given quesiton, the diagonal of a cube with side length s is given by the formula d = s√3.

Here,

As mentioned in the question, we have given a cube with a length of its side is 5 cm.

We know that the diagonal of a cube with side length s is given by the formula d = s√3.
Substituting s=5 into this formula, we get:

d = s√3.

d = 5√3

Rounding to the nearest tenth, we get d = 8.7 cm.

Therefore, the length of the diagonal of a cube with a side length of 5 cm is approximately 8.7 cm.

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the distance across the center of a circle is called the?

Answers

Hello there!


The distance from one side of a circle to the other going through the center is called the Diameter.


I hope that helps!

Triangle LMN has vertexes at L(-1, -6), M(1, -6), and N(1, 1). Find the measure of angle L to the nearest degree.

Answers

check the picture below

is a right-triangle, and you can pretty much see how long "y" and "x" are.

make sure your calculator is in Degree mode.

If a baseball team's ratio of wins to losses is 5 to 4, what is the ratio of wins to total games played?

Answers

I believe it's 5 to 9 since out of 9 games they win 5 and lose 4. This doesn't account for draws or anything, though.

There are five boys and five girls in a class. The teacher randomly selects three different students to answer questions. The first student is a girl, the second student is a boy, and the third student is a girl. Find the probability of this occuring.

Answers

Final answer:

The probability of selecting a girl, then a boy, and then another girl from a class with 5 girls and 5 boys is 10.42%.

Explanation:

The probability of a specific sequence of students being selected in a random draw can be calculated by multiplying the probabilities of each event occurring in succession. Since there are five boys and five girls in the class, the probability of drawing a girl first is 5/10, or 1/2. After drawing one girl, there are now four girls and five boys left, so the probability of drawing a boy second is 5/9. Finally, with one girl and one boy already picked, there are three girls and four boys left, making the probability of drawing a girl third 3/8.

To find the overall probability, we multiply these individual probabilities:

Probability = (First girl drawn) × (Second boy drawn) × (Third girl drawn)
Probability = (1/2) × (5/9) × (3/8)
Probability = (1 × 5 × 3) / (2 × 9 × 8)
Probability = 15 / 144
Probability = 0.1042 or about 10.42%

Final answer:

The probability of the teacher randomly selecting a girl, a boy, and another girl from a class of 5 boys and 5 girls is 5/6.

Explanation:

To find the probability of the teacher randomly selecting three different students, we need to consider the number of possible outcomes and the number of favorable outcomes. In this case, there are 10 students to choose from and the teacher needs to select one girl, one boy, and another girl. To calculate the probability, we divide the number of favorable outcomes by the number of possible outcomes.

The number of favorable outcomes is 5 for the first girl, 5 for the boy, and 4 for the second girl (since the first girl has already been selected). So the total number of favorable outcomes is 5 x 5 x 4 = 100.

The number of possible outcomes is the total number of ways to choose 3 students from the 10 available. This can be calculated using the combination formula: C(10, 3) = 10! / (3!(10-3)!) = 120.

Therefore, the probability of selecting a girl, a boy, and another girl is 100/120 = 5/6.

Find the GCF of the first two terms and the GCF of the last two terms of the polynomial. 5h^3+20h^2+4h+16

Answers

The GCF of the first two terms: 5h²
The GCF of the last two terms: 4

5h³ and 20h² 

Both of these terms are divisible by 5. (constant)
Both of these terms also have at least 2 h's. (variable)

4h and 16

Both of these terms are divisible by 4. 
Only one term has a variable, so that has to be left out.



If a=6 and b=5 what is the value of (A2-b2)2

Answers

(a^2-b^2)^2

(36-25)^2

11^2

121
(a²-b²)²
a=6 and b=5
(6²-5²)²

pemdas, so simplify inside first
(36-25)²
(11)²
121

Graph the hyperbola with equation quantity x plus four squared divided by sixteen minus the quantity of y plus three squared divided by twenty five = 1.

Answers

Please see the attached figure. This is how you draw a hyperbola. Its general formula is:

(x-h)²/a² - (y-k)²/b² = 1, where

(h,k) is the center
a is the semi-major axis
b is the semi-minor axis

The given equation is

(x+4)²/16 - (y+3)²/25 = 1

So, from the general form we can deduce that,
Center(-4,-3)
a = 4
b = 5

So, the first point we can plot is the centerpoint. Next, you draw the two intersecting lines. Their slopes are +/- b/a. Thus, it corresponds to +/- 5/4. Using this slope, we can find the equation of the two lines by using the slope and the center.

-3 = +5/4 (-4) + b ---> b= 2
-3 = -5/4 (-4) + b ---> b= -8

So, you plot the equations y=5/4x + 2 and y = -5/4 x -8 by assigning values of x and plotting them against y. Then, the vertex of the hyperbolas are 4 units from the center, denoted by the green dots. The hyperbola is shown in the next picture.

Give an example of a function that is integrable on the interval [-1,1], but not continuous on [-1,1]. explain.

Answers

With an absolute value somewhere in the formula, you can create a discontinuous function.

how about f(x) = |x|/x

It jumps from -1 to +1 at x=0, yet it can be integrated on [-1,1]. The surface is 2.

How many days are between march the 15th and august the 15th?

Answers

March has 31 days so 15-31=16
August the 15 is 15 days into the month.
You add 16+15 which equals 31 days.

Answer:21 weeks and 6 days

Step-by-step explanation:

lol im late its 2021

Melissa has three different positive integers. she adds their reciprocals together and gets a sum of 1. what is the product of her integers?

Answers

First let us assign the three positive integers to be x, y, and z.

From the given problem statement, we know that:

(1/x) + (1/y) + (1/z) = 1


Without loss of generality we can assume x < y < z.

We know that:

 

1 = (1/3) + (1/3) + (1/3)

 

Where x = y = z = 3 would be a solution

 

However this could not be true because x, y, and z must all be  different integers.  And x, y, and z cannot all be 3 or bigger than 3 because the sum would then be less than 1.  So let us say that x is a denominator that is less than 3.   So x = 2, and we have:

 

(1/2) + (1/y) + (1/z) = 1

 

Therefore

 

(1/y) + (1/z) = 1/2

 

We  also know that:

 

(1/4) + (1/4) = (1/2)

 

and y = z = 4 would be a solution, however this is also not true because y and z must also be different. And y and z cannot be larger than 4,  so y=3, therefore

 

(1/2) + (1/3) + (1/z) = 1

 

Now we are left by 1 variable so we calculate for z. Multiply both sides by 6z:

3z + 2z + 6 = 6z

z = 6

 

Therefore:

 

(1/2) + (1/3) + (1/6) = 1

 

so {x,y,z}={2,3,6} 

 

Final answer:

The product of Melissa's integers is 120.

Explanation:

The product of Melissa's integers is 120.

Let the integers be a, b, and c.

According to the given information, 1/a + 1/b + 1/c = 1.

By finding common denominators and simplifying, you can determine that a * b * c = 120.

Which of the following is FALSE? The diagonals of a parallelogram bisect each other. The diagonals of a rhombus bisect each other. The diagonals of a square bisect each other. The diagonals of a kite bisect each other

Answers

the diagonals of  rhombus bisect each other

Answer:

The diagonals of a kite bisect each other

Step-by-step explanation:

Let analyse all possible answer:

a. The diagonals of a parallelogram bisect each other

True, it is one of the properties of a parallelogram

b. The diagonals of a rhombus bisect each other

True, In any rhombus, the diagonals (lines linking opposite corners) bisect each other at right angles (90°). That is, each diagonal cuts the other into two equal parts, and the angle where they cross is always 90 degrees.

c. The diagonals of a square bisect each other.

True, it is one of the properties of a square

d. The diagonals of a kite bisect each other

Wrong, because we do not know what shape of the kite is, it can have a really strange shape that we can not identify where the diagonals are as you can see in the attached photo.  

NEED HELP!!!!!!!!!!!!!!!

Which factorizations can be used to identify the real zeros of the function f(x)=-20x^2+23x-6 ?

A. (-10x+2)(2x+3)
B. -(10x+2)(2x-3)
C. -(4x-3)(5x+2)
D. -(4x-3)(5x-2)

Answers

It's D, it's the only one where it has a -6 at the end other than A, but if you look at the A when distributed there isn't a 23x

Answer:

Option D. [tex]-(4x-3)(5x-2)[/tex]

Step-by-step explanation:

we have

[tex]f(x)=-20x^{2}+23x-6[/tex]

Equate the function to zero

[tex]-20x^{2}+23x-6=0[/tex]

Group terms that contain the same variable, and move the constant to the opposite side of the equation

[tex]-20x^{2}+23x=6[/tex]

Factor the leading coefficient

[tex]-20(x^{2}-(23/20)x)=6[/tex]

Complete the square. Remember to balance the equation by adding the same constants to each side

[tex]-20(x^{2}-(23/20)x+(529/1,600))=6-(529/80)[/tex]

[tex]-20(x^{2}-(23/20)x+(529/1,600))=-(49/80)[/tex]

[tex](x^{2}-(23/20)x+(529/1,600))=(49/1,600)[/tex]

Rewrite as perfect squares

[tex](x-(23/40))^{2}=(49/1,600)[/tex]

[tex](x-(23/40))=(+/-)(7/40)[/tex]

[tex]x=(23/40)(+/-)(7/40)[/tex]

[tex]x=(23/40)(+)(7/40)=30/40=3/4[/tex]

[tex]x=(23/40)(-)(7/40)=16/40=2/5[/tex]

therefore

[tex]-20x^{2}+23x-6=-20(x-(3/4))(x-(2/5))[/tex]

[tex]-20x^{2}+23x-6=-(5)(4)(x-(3/4))(x-(2/5))[/tex]

[tex]-20x^{2}+23x-6=-(4x-3)(5x-2)[/tex]

Jonathan deposits $2000 into a bank account that pays 7% annual interest compounded annually. This means the bank pays him 7% of his account balance as interest at the end of each year, and he leaves the original amount and the interest in the account.
1. Write a recursive formula to model the situation described above. Use A0 to represent the initial amount invested. Then describe An, the next year’s balance, in terms of the current year’s balance, An-1.

Answers

For us to get the formula that models the above statement, we shall use the formula for compound interest. Compound interest is given by:
A=p(1+r/100)^n
where;
A=future amount=An
p=current amount=A0
r=rate=7%
n=time= 1 year
thus rewriting our formula we shall have:
An=A0(1+r)^n
The above is the model describing the information given for future cash flow;
hence, the amount in 1 year will be:
An=A0(1+0.07)^1
An=2000(1.07)^1
An=$2,140

What is the 12th term of the arithmetic sequence where a1 = 5 and a6 = 20?

Answers

an=a1+d(n-1)
an=nth term
a1=first term
d=common differnce
n=which term

alrighty, a1=5

neat
an=5+d(n-1)
given a6=20
20=a6=5+d(6-1)
20=5+d(5)
20=5+5d
minus 5 both sides
15=5d
divide both sides by 5
3=d

so
an=5+3(n-1) is the formula for the nth term


12th term
a12=5+3(12-1)
a12=5+3(11)
a12=5+33
a12=38

the 12th term is 38

Can you use matrix multiplication with a matrix with three rows and a matrix with two columns

Answers

Maybe.  if a mxn matrix is multiplied by a nxp matrix, you can and will get a mxp matrix result.

Use the table below to answer this question:

x y
0 2
1 -1
2 -6

Find the average rate of change for the given function from x = 0 to x = 2.

Answers

(y_final-y_start)/(x_final-x_start) always! :) that easy

(-6-2)/(2-0) = -4

You probably know that if the interval was pretty small, between 0 and 0.0001, it would take you to the concept of slope and derivatives, but average change is just ignoring anything in between x=0, and x=2 (it could go up/down million times, and still the answer would be -4)

hope it helps

which of the following are not techniques used in geometric constructions with paper folding. Check all that apply
A. Creating arcs and circles work the compass
B. Drawing line segments
C. Measuring lengths of line segments by folding the paper and matching the endpoints
D. Folding the paper and aligning marks seen through the paper

Answers

There are two correct answers which are not techniques used in geometric constructions with paper folding and these are:

 

A. Creating arcs and circles work the compass

C. Measuring lengths of line segments by folding the paper and matching the endpoints

 

In geometric folding, a straight line becomes a crease or a fold. This is achieved by a person by folding a piece of paper and flattening the crease rather than drawing lines to make a guide. Therefore this means that shapes like arcs, curves, circles by using the compass, and measurement of line segments are not used. However, constructions using compass have a long history in Euclidean geometry.

The following are not techniques used in geometric constructions with paper folding:

A. Creating arcs and circles with the compass.

C. Measuring lengths.

What is a geometric construction?

A geometric construction can be defined as a process that is used to draw angles, lines, and other geometric figures (shapes), especially through the use of only a compass and straightedge such as a ruler without measurements.

In Geometry, the techniques that should be used in geometric constructions with paper folding include the following:

Drawing line segments.Folding the paper and aligning marks that are seen through the paper.

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5,200 g divided by 583.1 mL

Answers

there is 1 gram per 1 milliliter so just divide them

5200/583.1 = 8.91785

you don't say if it needs to be rounded to a certain amount

 so since the mL has one decimal place

 round to 8.9mL

Which expression is equivalent to (2g^5)^3/(4h^2)^3

Answers

[tex] \cfrac{(2g^5)^3}{(4h^2)^3} = \cfrac{2^3 \cdot g^{5\cdot3}}{4^3 \cdot h^{2\cdot3}} = \cfrac{8 g^{15}}{64 h^{6}} =\cfrac{g^{15}}{8h^{6}} [/tex]

First option

Answer:

Step-by-step explanation:

It’s A

Earyn owns French Twist Hair Salon. She charges $35 for a cut an $120 for a cut and color combo. Yesterday she had seven clients and earned $500. Let x represent only the clients that got a cut and y represent the clients that got a cut and color combo.
Which of the following equations could be used to represent this situation.

1. y=7-x
2. x + y= 500
3. 120x + 35y= 500
4. (35+120) (x + y)= 500
5. 35x + 120y= 500

Check all that apply

Answers

The answer is the last one:
35x + 120y= 500

Always the last one! lol

Answer:

Option 5th is correct

[tex]35x+120y = 500[/tex]

Step-by-step explanation:

Here, x represents only the clients that got a cut and y represent the clients that got a cut and color combo.

As per the statement:

Earyn owns French Twist Hair Salon. She charges $35 for a cut an $120 for a cut and color combo.

" Charges $35 for a cut" translated to 35x

"$120 for a cut and color combo" translated to 120y

It is also given that yesterday she had seven clients and earned $500.

⇒[tex]35x+120y = 500[/tex]

therefore, an  equations could be used to represent this situation is, [tex]35x+120y = 500[/tex]

Flying against the wind, an airplane travels 2280 km in 4 hours. Flying with the wind, the same plane travels 6650 km in 7 hours. What is the rate of the plane in still air and what is the rate of the wind?

Answers

speed = dis / time

let plane speed in still air is X  and air speed Y

so,  X-Y = 2280/4  = 570 km/h

and X+Y = 6650/7 = 950 km/h

so, X = (570 + 950) / 2 = 760 km/h 

and Y = 950- 760 = 190 km/h 

:)

Find the volume of a cone with radius 30 in and slant height 50 in.

Answers

The volume of cone is 37,680 cubic inch.

What is volume?

Space is used by every three-dimensional object. This space is estimated concerning its volume. The volume of an object in three-dimensional space is the amount of space it occupies within its boundaries. The capacity of the object is another name for it.

An object's volume can help us figure out how much water is needed to fill it, like how much water is needed to fill a bottle, aquarium, or water tank.

Given radius of cone = r  = 30 inch

slant height = l = 50 inch

volume of cone = V = 1/3πr²h

relation between height, radius, and slant height is given by

l² = h² + r²

where l = slant height, h = height and r = radius

h = [tex]\sqrt{l^{2} - r^{2} }[/tex]

h = [tex]\sqrt{50^{2} - 30^{2} }[/tex]

h = √1600 = 40 inch

V = 1/3πr²h = 1/3π × (30)² × 40

V = (3.14 × 900 × 40)/3

V = 37,680 cubic inch

Hence the volume is 37,680 cubic inch.

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A student is running a 3-kilometer race. He runs 1 kilometer every 2 minutes. Select the function that describes his distance from the finish line.

Answers

Final answer:

A function that describes a student's distance from the finish line in a 3-km race, running 1 km every 2 minutes, is a linear function represented by the formula f(t) = 3 - 0.5t, where t is time in minutes. This function shows a direct and proportional decrease in distance as time progresses.

Explanation:

The question asks for a function that describes the student's distance from the finish line in a 3-kilometer race, given that they run at a constant pace of 1 kilometer every 2 minutes. To find this function, we can use the concept of a linear relationship between time and distance.

Since the student is 3 kilometers away from the finish line at the start and runs 1 kilometer every 2 minutes, we can set up the function f(t) = 3 - 0.5t, where t represents time in minutes. This function decreases linearly because for every increase of 2 minutes in time, the distance from the finish line decreases by 1 kilometer. After 6 minutes, the function will read f(6) = 0, indicating that the student has reached the finish line.

An example will make this clear: After 4 minutes, the student has run 2 kilometers (since 4 minutes is twice 2 minutes, and the student runs 1 kilometer every 2 minutes), so his distance from the finish line is 3 km - 2 km = 1 km. We use f(t) = 3 - 0.5t and substitute t = 4 to get f(4) = 3 - 0.5(4) = 1 kilometer from the finish line.

The midpoint of A (-4, 2) and B(8, 5) is

Answers

[tex]\bf \textit{middle point of 2 points }\\ \quad \\ \begin{array}{lllll} &x_1&y_1&x_2&y_2\\ % (a,b) &({{ -4}}\quad ,&{{ 2}})\quad % (c,d) &({{ 8}}\quad ,&{{ 5}}) \end{array}\qquad % coordinates of midpoint \left(\cfrac{{{ x_2}} + {{ x_1}}}{2}\quad ,\quad \cfrac{{{ y_2}} + {{ y_1}}}{2} \right) \\\\\\ \left(\cfrac{{{ 8}} -4}{2}\quad ,\quad \cfrac{{{ 5}} + {{ 2}}}{2} \right)[/tex]

Answer:  The midpoint of the points A(-4, 2) and B(8, 5) is M(2, 3.5).

Step-by-step explanation:  We are given to find the midpoint of the points A(-4, 2) and B(8, 5).

We know that

the co-ordinates of the midpoint of the points (a, b) and (c, d) are given by

[tex]M=\left(\dfrac{a+c}{2},\dfrac{b+d}{2}\right).[/tex]

Therefore, the co-ordinates of the midpoint of the points (-4, 2) and B(8, 5) will be

[tex]M=\left(\dfrac{-4+8}{2},\dfrac{2+5}{2}\right)=\left(\dfrac{4}{2},\dfrac{7}{2}\right)=(2,3.5).[/tex]

Thus, the midpoint of the points A(-4, 2) and B(8, 5) is M(2, 3.5).

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