Can you help with my Precalculus?

Question

the question reads “a box is formed by cutting squares out of the corners of a flat piece of metal and folding the sides up. What size cuts should I make to a 14 inch by 20 inch piece to get a volume of 270 inches cubed?”

 

im so confused. Please help me out

Answer 1

(14-2x)(20-2x)x = 270

solve for x

it's a cubic, hard to solve

so just graph it and find the x intercepts that make sense

about 1.2, 4.2, and another x intercept that is far too large

go with about 1.2 inch square or 4.2 inch square