Write the Volume as an Algebraic Expression

A right pyramid with a square base has a base length of [tex]x[/tex] inches, and the height is two inches longer than the length of the base. Which expression represents the volume in terms of [tex]x[/tex]?

A. [tex]\frac{x^2(x+2)}{3}[/tex] cubic inches
B. [tex]\frac{x(x+2)}{3}[/tex] cubic inches
C. [tex]\frac{x^3}{3}+2[/tex] cubic inches
D. [tex]\frac{x^3+2}{3}[/tex] cubic inches



Answer :

To find the expression that represents the volume of a right pyramid with a square base where the base length is [tex]\(x\)[/tex] inches and the height is two inches longer than the base length, we can follow these steps:

1. Identify given quantities:
- Base length of the pyramid = [tex]\(x\)[/tex] inches.
- Height of the pyramid = [tex]\(x + 2\)[/tex] inches (since it's two inches longer than the length of the base).

2. Formula for the volume of a pyramid:
The formula to calculate the volume of a pyramid is given by:
[tex]\[ \text{Volume} = \frac{\text{Base Area} \times \text{Height}}{3} \][/tex]

3. Calculate the base area:
For a pyramid with a square base, the area of the base ([tex]\(A\)[/tex]) is the side length squared:
[tex]\[ \text{Base Area} = x^2 \][/tex]

4. Substitute the known values into the volume formula:
Now, substitute the base area and the height into the volume formula:
[tex]\[ \text{Volume} = \frac{x^2 \times (x + 2)}{3} \][/tex]
Simplifying this expression, we get:
[tex]\[ \text{Volume} = \frac{x^2(x + 2)}{3} \][/tex]

So, the expression that represents the volume of the pyramid in terms of [tex]\(x\)[/tex] is:
[tex]\[ \boxed{\frac{x^2(x + 2)}{3}} \][/tex]

This corresponds to the first option given in the list:
[tex]\[ \frac{x^2(x+2)}{3} \text{ cubic inches} \][/tex]

Thus, the correct expression representing the volume of the pyramid is:
[tex]\[ \frac{x^2(x + 2)}{3} \text{ cubic inches} \][/tex]