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3 years ago

if a rectangle has an area of 30 square meters and a perimeter of 34 meters . what is the dimensions of the rectangle?

1 answer:

7 0

P=2(L+W) and P=34 so

2(L+W)=34

L+W=17 so we can say

L=17-W

A=LW using L from above

A=(17-W)W

A=17W-W^2 and A=30 so

30=17W-W^2

W^2-17W+30=0

W^2-2W-15W+30=0

W(W-2)-15(W-2)=0

(W-15)(W-2)=0

So the dimensions of the rectangle are 15 meters by 2 meters.

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Let x=ab=ac, and y=bc, and z=ad.

Since the perimeter of the triangle abc is 36, you have:

Perimeter of abc = 36
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If you prefer a less algebraic reasoning:

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D) $ 2,550.00 at 3 1/4 interest for 4 years

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