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Volume is 10x3 + 67x2 + 30x − 72, length is 5x − 4, width is 2x + 3

User Relativity
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1 Answer

4 votes

Answer:

height = x + 6

Explanation:

Volume = length x width x height

V = 10x³ + 67x² + 30x − 72

length = 5x - 4 and width = 2x + 3

So length x width = (5x - 4 ) x (2x + 3)

Using the FOIL method:

= (5x)(2x) + (5x)(3) + (-4)(2x) + (-4)(3)

= 10x² + 15x - 8x - 12

= 10x² + 7x -12

So to find height, divide Volume by (length x width)

10x³ + 67x² + 30x − 72 ÷ 10x² + 7x -12

Use polynomial long division. See image ( I did the best I could to capture the process)

The answer is x + 6

To verify
Multiply (5x-4) (2x + 3) (x + 6) = 10x³ + 67x² + 30x − 72

Volume is 10x3 + 67x2 + 30x − 72, length is 5x − 4, width is 2x + 3-example-1
User Ryan Sayles
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