posted by Kaylee on .
A rectangular pad of concrete is outlined by a 52-m stripe of paint. Find the dimensions of this pad if the surface area is 168m^2.
drwls: Is there any way you can explain why you did what you did? I don't understand. You had this:
2 (L + W) = 52 (perimeter)
L*W = 168 (area)
2*168/W + 2W = 52
168/W + W = 26
W^2 - 26W = 168
(W-14)(W-12) = 0
W = 14 or 12 m
If W = 12, L = 14 and vice versa
The pad dimensions are 14 x 12 m.
The first two equation are a math statement of what the given is (Perimeter, area).
The rest is algebra, you can do that however you see fit. DrWLS did it by substitution.