SOLUTION: what rectangles dimensions has a area of 45 ft. and a perimeter of 36 ft. ?

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Question 377927: what rectangles dimensions has a area of 45 ft. and a perimeter of 36 ft. ?
Answer by sophxmai(62) About Me  (Show Source):
You can put this solution on YOUR website!
xy=45
2x+2y=36
x=%28-2y%2B36%29%2F2

xy=45
y%28%28-2y%2B36%29%2F2%29=36
y(-y+18)=36
-y%5E2%2B18y=36
-y%5E2%2B18y-36=0
(y-15)(y-3)=0
y=3,15

When y is 3, x is:
xy=45
x(3)=45
x=15

When y is 15, x is:
xy=45
x(15)=45
x=3

Dimensions of the rectangle can be 3ft by 15 ft or 15ft by 3ft