solve each system by elimination 3x-y=-2 -2x+y=2

Answer:

380 different ways

Step-by-step explanation:

We can solve this problem using a permutation formula, as the order in a group of two students matter.

So, for this problem, we have 20 students and want to form groups of 2, so we have a permutation of 20 choose 2:

P(20,2) = 20! / (20-2)! = 20! / 18! = 20 * 19 = 380 different ways

Another way to solve this problem is:

For the first student being chose, we have 20 students available, and for the second student, we have just 19, as one was already chose, so the number of ways to choose these two students is 20 * 19 = 380

Answer:

1,055.58 in^3

Step-by-step explanation:

The volume of a cone is given by

V = 1/3 pi r^2 h

We need the radius

r = d/2 = 12/2 =6

V = 1/3 (pi) (6)^2 *28

Using the pi button on the calculator

   =1055.575132

Rounding to 2 decimal places

 1,055.58 in^3

m=-2-4/3-4=-6/-1=6

y-4=6(x-4)

y=6x-20

Answer:

subtract 3 each term

Step-by-step explanation:

Answer:

f(x)=1200(1.04)^n

Step-by-step explanation:

Answer:

31.5789%

Step-by-step explanation:

Answer:

24%

Step-by-step explanation:

If you use the "is over of" form.

"19 is what percent of 25"

You'd set it up like this:

[tex]\frac{19}{25}[/tex]=[tex]\frac{x}{100}[/tex]

Then cross multiply:

19 times 100 = 1900

25 times x = 25x

Divide 25 into 1900 and get 76.

That is the percent (%) of what 19 is of 25.

BUT we want the space in between the numbers.

To get that, we subtract 100 - 76.

(100 is the whole 100%)

This gives you 24%

Answer:

113.1

there u go

Answer: 34

Step-by-step explanation:

(x+22) + x = 90

Given that angles A and B are complementary. Angle A is (x + 22) degrees. Angle B is x degrees. The value of x is 34°.

When the sum of two angles is equal to 90 degrees, they are called complementary angles.

(x + 22) + x = 90

2x + 22 = 90

2x = 68

x = 34

Learn more about complementary angles here

https://brainly.com/question/5708372

#SPJ3

Answer:

Solving the expression, it is equal to 48. But it you want and expression equal to 48:

4 x 12 can be the answer.

Step-by-step explanation:

[tex]$4\cdot \left[\left(12\:+\:4\right)\:-\:\left(\frac{12}{3}\right)\right]$[/tex]

[tex]4\left(12+4-4\right)[/tex]

[tex]4 \cdot 12\\48[/tex]

Answer:

Answer choice A

Step-by-step explanation:

For the first letter, there are 26 options, as there are for the second and third letter. For each of the three numbers, there are 10 digits to choose from. Therefore, 26*26*26*10*10*10=17,576,000, or answer choice A. Hope this helps!

Option (A) the number of different ways of license plate arrangements are 17,576,000 is the correct answer.

A permutation is an arrangement of objects in a definite order. It is a mathematical technique that determines the number of possible arrangements in a set when the order of the arrangements matters.

For the given situation,

A state license plate consists of three letters followed by three digits.

There are 26 letters from a to z and 10 digits from 0 to 9.

The license plate consists of three letters and three digits so the possibility of arrangements are

⇒ [tex](26)(26)(26)(10)(10)(10)[/tex]

⇒ [tex]17576000[/tex]

Hence we can conclude that option (A) the number of different ways of license plate arrangements are 17,576,000 is the correct answer.

Learn more about permutations here

https://brainly.com/question/14767366

#SPJ2

Answer:

11 pens weigh 53.43 grams.

2 pens weigh X grams.

We have:

11/53.43 = 2/X

=> X = 2 x 53.43/11 = 9.72 grams

Hope this helps!

:)

Answer:

23. Length = 21 feet, Width = 3 feet

24. Larger Angle = 162 degrees, Smaller Angle = 18 degrees

Step-by-step explanation:

23.

Let us say:                                                                                                      l ⇒ length of the rectangular pool, w ⇒ width of the rectangular pool

According to the problem we could formulate two equations as such:

2l + 2w = 48,

l = 15 + 2w

Now let us solve for the dimensions;

First convert the two equations to standard form:

2l + 2w = 48,

l - 2w = 15

Using process of elimination:

  2l + 2w = 48

+   l  - 2w = 15

Simplify:

3l = 63,

length = 21 feet

Substitute this value of length into the second equation.....:

21 - 2w = 15

.......And simplify:

-2w = -6,

width = 3 feet

24.

Let us say:                                                                                                      L ⇒ larger angle, S ⇒ smaller angle,

According to the problem we could formulate two equations as such:

L + S = 180,

L = 9S

Now let us solve for the angles;

Let us here use substitution:

(9S) + S = 180

Simplify:

10S = 180,

Smaller Angle = 18 degrees

Substitute this value of the smaller angle into the second equation.....:

L = 9(18)

.......And simplify:

Larger Angle = 162 degrees

Answer:

4

Step-by-step explanation:

Trust me

Answer:

2 + 2 = 4

Step-by-step explanation:

Are you sure?  Is this a trick?  Or is the "+"  a different kind of plus?

Answer:

(a + 8) (a + 8)

Step-by-step explanation:

a² + 16a + 64

a² + 8a + 8a + 64

a(a + 8) + 8(a + 8)

(a + 8) (a + 8)

We have been a right triangle. We are asked to find the missing length of the given triangle.

We can see that our given triangle is 30-60-90 triangle.

We know that the lengths of the sides of a 30-60-90 triangle are in the ratio [tex]1:\sqrt{3}:2[/tex].

If the side opposite to 30 degree is [tex]n[/tex], then the side opposite to 60 degree angle will be [tex]\sqrt{3}n[/tex] and side opposite to hypotenuse will be [tex]2n[/tex].

We can see that side corresponding to hypotenuse is 6 that is [tex]2n=6[/tex].

Let us solve for n.

[tex]\frac{2n}{2}=\frac{6}{2}[/tex]

[tex]n=3[/tex]

The side corresponding to 30 degree angle will be half of 6 that is 3. Therefore, the value of y is 3.

The value of x will be [tex]3\sqrt{3}[/tex] as it is side corresponding to 60 degree angle.

Answer:

[tex]P(90<X<110)=P(\frac{90-\mu}{\sigma}<\frac{X-\mu}{\sigma}<\frac{110-\mu}{\sigma})=P(\frac{90-100}{15}<Z<\frac{110-100}{15})=P(-0.67<z<0.67)[/tex]

[tex]P(-0.67<z<0.67)=P(z<0.67)-P(z<-0.67)[/tex]

[tex]P(-0.67<z<0.67)=P(z<0.67)-P(z<0.67)=0.749-0.251=0.498[/tex]

Step-by-step explanation:

Let X the random variable that represent the IQ scores, and for this case we know the distribution for X is given by:

[tex]X \sim N(100,15)[/tex]  

Where [tex]\mu=100[/tex] and [tex]\sigma=15[/tex]

We want to find this probability

[tex]P(90<X<110)[/tex]

And we can use the z score formula given by:

[tex]z=\frac{x-\mu}{\sigma}[/tex]

If we apply this formula to our probability we got this:

[tex]P(90<X<110)=P(\frac{90-\mu}{\sigma}<\frac{X-\mu}{\sigma}<\frac{110-\mu}{\sigma})=P(\frac{90-100}{15}<Z<\frac{110-100}{15})=P(-0.67<z<0.67)[/tex]

And we can find this probability with this difference:

[tex]P(-0.67<z<0.67)=P(z<0.67)-P(z<-0.67)[/tex]

And in order to find these probabilities we can use the normal standard table or excel and we got.  

[tex]P(-0.67<z<0.67)=P(z<0.67)-P(z<0.67)=0.749-0.251=0.498[/tex]

Answer:

C

Step-by-step explanation:

The solution is: quadratic; y = 2.5x^2, this function best models the data.

Option (1)

Function, in mathematics, an expression, rule, or law that defines a relationship between one variable (the independent variable) and another variable.

here, we have,

given that,

x               -2              -1                 0                    1                   2

y               10            2.5                0                  2.5                3.0

Ist difference,

d_1 = -7.5  

d_2= -2.5

d_3 = 2.5

d_4 = 7.5

2nd difference,

x_1  = 5

x_2 = 5

x_3 = 5

Since 2nd difference is common, given table represents a quadratic equation.

Let the equation is,

y = ax²+ bx + c

For a point (0, 0) passing through the quadratic equation,

0 = c

Therefore, quadratic equation is y = ax² + bx

Since ordered pair (-1, 2.5) passes through the graph of the function,

2.5 = a(-1)² + b(-1)

a - b = 2.5 ------(1)

For another point (1, 2.5)

2.5 = a(1)² + b(1)

a + b = 2.5 ------(2)

By adding equations (1) and (2),

2a = 5

a = 2.5

and from equation (2)→ y = 0

Therefore, equation of the quadratic function given in the table is y = 2.5x²

Option (1) is the answer.

Hence, The solution is: quadratic; y = 2.5x^2, this function best models the data. i.e. Option (1)

To learn more on function click:

brainly.com/question/21145944

#SPJ7

Complete question:

Graph the data in the table. Which kind of function best models the data? Write an equation to model the data. quadratic; y = 2.5x2 linear; y = 2.5x quadratic; y = –2.5x2 exponential; y = 2.5x

Answer: 3.708 * 10^4

Step-by-step explanation:

Answer:

i think thats d sorry if incorrect

Step-by-step explanation:

Answer:

  -$500

Step-by-step explanation:

The expected value of a payment from the policy is ...

  $500,000 × 0.002 = $1000

Since the business pays $1500 for the policy, the expected value to the business is ...

  $1000 - 1500 = -$500 . . . per year

_____

Of course, the expected value to the insurance company is $500 per year.

_____

We have computed on the basis of 1 claim per year. If we consider the possibility of multiple independent claims, then the expected payment from the insurance goes up by a factor of 1/(1 -0.002) ≈ 1.002004008016.... This has the effect of increasing the expected value by $2.00 per year to -$498.

Answer:

25 by 17

Step-by-step explanation:

9x2=18

84=18= 102

102/6 = 17 (width)

17x2-9=25 (length)

Answer:

Percy is incorrect

Step-by-step explanation:

I plugged in 9 and 8 for x and both of them did NOT solve it. The only number I know of that can solve it is -7.       -7^2=49

                                             -7 multiplied by 7 =-49

                                                      (49) + (-49) + 12 = 12

Answer:

Percy was not correct.

Percy did not write the equation in standard form before factoring.

The correct solutions are 0 and –7.

The equation should have first been written as x2 + 7x = 0 before factoring.

The solutions 8 and 9 do not make the equation true.

Step-by-step explanation:

The answer would be M= 23/2 or 11.5.

Answer:is yes

Step-by-step explanation:

no

Answer:

A= 8.182

B= 8

Step-by-step explanation:

Answer:

sales tax is  31 dollars and 53 cents

Step-by-step explanation:

You want the sales tax in dollars and cents.

so

Sales tax = 6% * $525.50 = 0.06* $525.5 =  $31.53

Answer:

For the first one it would be 84

Second: 45

Step-by-step explanation:

First one: 7 times 12.

Second: add 30 and 30 together which is 60. Then divide 30 in half which is 15. Then add 15 to 30.

Answer:

3. 84 inches

4. 75 miles

Step-by-step explanation:

3.

Scale = 1/12 × actuall

7 = 1/12 × actual

actual = 7 × 12 = 84 inches

4.

Map : actual

1 in : 30 miles

2.5 in : X miles

X/2.5 = 30/1

X = 2.5×30 = 75 miles

Answer:

B-y=2

Step-by-step explanation:

y= 2x-2

X=2

y=2(2)-2

y=4-2

y=2

Answer:

The answer to this question is maximum

Answer:

Maximum

A downward parabola will have the highest point at the very top, so it will have a maximum.