## anonymous one year ago Find the volume of a rectangular prism if the length is 2x, the width is 4x2, and the height is 2x^2 + x + 7. Use the formula V = l ⋅ w ⋅ h, where l is length, w is width, and h is height, to find the volume.

1. anonymous

You have to multiply V = (2x)(4x²)(2x² + x + 7) Start by multiplying 2x and 4x² Then distribute the result through the parentheses

2. anonymous

but can you multiply those two?... because they have different exponents ?

3. anonymous

you can multiply if they have the same base. (You just can't add or subtract with different exponents.) When multiplying, add the exponents. When subtracting subtract them. For example $x^5 \times x^6=x^{5+6}=x^{11}$ $\frac{ x^9 }{ x^4 }=x^{9-4}=x^5$

4. anonymous

For your problem you have $2x \times 4x^2=8x^3$

5. anonymous

okay so it would be (8x^3)(2x^2+x+7) ..?

6. anonymous

right, now distribute

7. anonymous

16x^5+8x^4+56x^3?

8. anonymous

yes :)

9. anonymous

yayy thank you!

10. anonymous

you're welcome

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