You need to sove two simultaneous equations.
L = length W = width
L = 3W + 8
2(L + W) = 128
Substitute 3W +8 for L in the last equation.
2[(3W+8)+ 2W] = 128
8W + 16 = 128
8W = 112
W = ?
L = 3W +8 = ?
A rectangle's length is 8 cm more than three times it's width. If the perimeter is 128 cm, find the length and width. What is the equation for this?
3 answers
L + L + W + W = 128
L - 8 = 3W
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Two equations. Two unknowns. Solve simultaneously.
L - 8 = 3W
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Two equations. Two unknowns. Solve simultaneously.
3 and 8
6 answers