SOLUTION: Question: The length of a rectangle is 3cm greater than its width. The area of the rectangle is 40cm^2. Find the length and width of the rectangle. I first tried x+3*x=40cm^2 b

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Question 987581: Question: The length of a rectangle is 3cm greater than its width. The area of the rectangle is 40cm^2. Find the length and width of the rectangle.
I first tried x+3*x=40cm^2 but as I tried to solve it, it didn't make sense since I got 18.5 cm for the width and 21.5 cm for the length. Please could you help explaining this, thank you.
Answer by vleith(2983) About Me  (Show Source):
You can put this solution on YOUR website!
You are on the rightrtrack. Just made a mistake on the length.
You have the width as x, and the length as 3x. The problem said the length was 3cm greater. Not 3 times greater. Use a length of (x+3) and then solve using the same techniques
40+=+x%2A%28x%2B3%29
40+=+x%5E2+%2B+3x
0+=+x%5E2+%2B+3x+-+40
0+=+%28x%2B8%29%28x-5%29
you can take in in from there