James had a rectangular piece of cardboard that was four times as long as it was wide. He wanted to use the cardboard to make a box with no lid. To do this, he first cut a 3-by-3 inch square out of each of the four corners of the piece of cardboard, as shown in the picture below. Then James folded the cardboard along the four dotted lines shown in the picture. This created an open box with a volume of 336 cubic inches. What was the width of the sheet of cardboard that james started with?
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let x be width then 4x is the length now make an expression for the volume of the box in terms of x and equate it to 336 solve this to find x
Okay so (4x)(x)(3)=336 or do you have to subtract the corners so (4x-6)(x)(3)=336?
hint: the width of the box will be ( x - 6 ) inches so what is the length?
4x-24?
no - you were correct with the length the first time its 4x - 6
Oh okay. woops. so then it would be L*W*H (3x-6)(x-6)(3)=336?
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