The formula for the volume of this rectangular prism is: V = x 3 + 5x 2 - 4x - 20

The length is x+5; the width is x+2; the height is unknown. Find an expression for the height.

Show all steps of your work for full credit.

Step-by-step explanation: Explanation:

If

L

,

H

and

W

represent the length, height and width of the prism, then the volume of the rectangular prism is :

V

=

L

.

H

.

W

(1)

Given :

V

=

x

3

+

11

x

2

+

20

x

−

32

;

(2)

W

=

(

x

−

1

)

;

H

=

(

x

+

8

)

.

Let

L

=

(

x

+

l

0

)

be the expression for the length, then the RHS of equation (1) becomes

L

.

H

.

W

=

(

x

−

l

0

)

(

x

+

8

)

(

x

−

1

)

,

=

(

x

+

l

0

)

(

x

2

+

7

x

−

8

)

=

(

x

+

l

0

)

(

x

2

+

7

x

−

8

)

=

x

3

+

(

7

+

l

0

)

x

2

+

(

7

l

0

−

8

)

x

−

8

l

0

(3)

Comparing this to the LHS of equation (1), we get the following set of equations to solve for

l

0

,

7

+

l

0

=

11

;

7

l

0

−

8

=

20

;

8

l

0

=

32

;

l

0

=

4

Therefore

L

=

(

x

+

4

)

x is greater than 5

step-by-step explanation:

2x+7 is greater than 17

    -7                           -7

2x is greater than 10

divide by 2 each side

x is greater than 5

care to share were the trapezoid shown is ?