SOLUTION: Mang Juan owns a rectangular lot. The perimeter of the lot is 90 m and its area is 450 m^2. What are the dimensions of the rectangular lot.

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Question 887008: Mang Juan owns a rectangular lot. The perimeter of the lot is 90 m and its area is 450 m^2. What are the dimensions of the rectangular lot.
Found 2 solutions by josgarithmetic, MathTherapy:
Answer by josgarithmetic(39617) About Me  (Show Source):
You can put this solution on YOUR website!
Another one much like this was asked not too long ago (today). Try this instead.

x and y are rectangle dimensions. Assume they are unknown but perimeter p and area A are known as given.

Find x and y.
2x%2B2y=p and xy=A.
Maybe p is an even number, and maybe it is not.

2y=p-2x
y=%28p-2x%29%2F2
and substituting into A,
x%28p-2x%29%2F2=A
x%28p-2x%29=2A
px-2x%5E2=2A
-2x%5E2%2Bpx-2A=0
highlight_green%282x%5E2-px%2B2A=0%29, and in practice not doing everything purely symbolically, maybe this is factorable
and maybe it is not factorable. Continuing, using the general solution for a quadratic equation
x=%28p%2B-+sqrt%28p%5E2-4%2A2%2A2A%29%29%2F%282%2A2%29
highlight%28x=%28p%2B-+sqrt%28p%5E2-16A%29%29%2F4%29.
One of these will makes sense and the other will not. Use the meaningful one.
Now just use the found x value to get the y value which corresponds.

Answer by MathTherapy(10552) About Me  (Show Source):
You can put this solution on YOUR website!

See problem # 886855