Mensurationhard · Past Paper
The length of a rectangular box is 2 units more than the width and the width is 3 units more than the height. If the total surface area is 112, find the height.
A2
B3
C4
D5
✓ Correct Answer: A — 2
Let h=x, w=x+3, l=x+5. 2[(x+5)(x+3) + (x+3)x + (x+5)x] = 112. (x²+8x+15 + x²+3x + x²+5x) = 56. 3x² + 16x - 41 = 0. Solving gives x=2.
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