SOLUTION: Please help me solve this problem: The length of a rectangle is 7 cm more than its width. If the length is increased by 2 cm and the width increased by 4 cm, the area will be in

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Question 631734: Please help me solve this problem:
The length of a rectangle is 7 cm more than its width. If the length is increased by 2 cm and the width increased by 4 cm, the area will be increased by 54 cm^2. Find the original length and width of the rectangle.
Thank you so much!

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

Please help me solve this problem:
The length of a rectangle is 7 cm more than its width. If the length is increased by 2 cm and the width increased by 4 cm, the area will be increased by 54 cm^2. Find the original length and width of the rectangle.
Thank you so much!

Let original width of rectangle be W
Then original length = W + 7
Increasing length by 2 makes it W + 7 + 2, or (W + 9) cm
Increasing width by 4 makes it (W + 4) cm

Original area = LW, or W(W + 7), or W%5E2+%2B+7W
Adjusted area = LW, or (W + 9)(W + 4), or W%5E2+%2B+13W+%2B+36

Since adjusted area is increased by 54+cm%5E2, then:
%28W%5E2+%2B+13W+%2B+36%29+=+%28W%5E2+%2B+7W%29+%2B+56
W%5E2+-+W%5E2+%2B+13W+-+7W+=+56+-+36

13W - 7W = 20
6W = 20

W, or original width = 20%2F6, or 10%2F3, or highlight_green%283%261%2F3%29 cm

Original length = W + 7, or 3%261%2F3+%2B+7, or 31%2F3, or highlight_green%2810%261%2F3%29 cm

You should be able to do the check!!

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