SOLUTION: Help.... Again!! The rectangle and the triangle have the same perimeter.Find the perimeter of each figure. The rectangle's measurements: the short side of the rectangle is x A

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Question 616028: Help.... Again!!
The rectangle and the triangle have the same perimeter.Find the perimeter of each figure.
The rectangle's measurements: the short side of the rectangle is x
And the long side is x-7
The triangle's measurements: one side is x+9
the other is x-7
and the third side is x+2
Please please help me! I tried usig the distributive property like this:
4(2x-7)= 3(3x
Answer by Earlsdon(6294) (Show Source):
You can put this solution on YOUR website!
The perimeter of a rectangle is:
P = 2(L+W) and L = x-7 and W = x Substitute:
P = 2(x-7+x) Simplify.
P = 2(2x-7)
P = 4x-14
The perimeter of a triangle is side1+side2+side3.
P = (x+9)+(x-7)+(x+2) Simplify.
P = 3x+4 These two perimeters are equal, so...
4x-14 = 3x+4 SUbtract 3x from both sides.
x-14 = 4 Add 14 to both sides.
x = 18
The perimeters are:
for the rectangle:
P = 4x-14 Substitute x = 18.
P = 4(18)-14
P = 72-14
P = 58
for the triangle:
P = 3x+4 Substitute x = 18.
P = 3(18)+4
P = 54+4
P = 58