Let the width = x
=>length = 2x-1
91= x(2x-1)=2x^2-x
2x^2-x-91=0
=(2x+13)(x-7)
=> x=-13/2=> no
=>x= 7 cm
The hint says that volume of a rectangular solid = l*w*h, where l = length, w = width, and h = height. Use this to solve for the height of the solid by plugging in the numbers you know.
You know that length, l = 2cm, width, w = 8cm, and, *EDITED* volume = 160 cm^3. Plug these values into the equation for volume (the hint) and solve for h, the height:
Volume = lwh
160 = (2)(8)(h)
160 = 16h
h = 10cm
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Answer: The height is 10 cm
