SOLUTION: The width of a rectangle is 7cm less than its length. Its area is 260cm squared. find the dimensions of the rectangle

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Question 877210: The width of a rectangle is 7cm less than its length. Its area is 260cm squared. find the dimensions of the rectangle
Answer by ben720(159) About Me  (Show Source):
You can put this solution on YOUR website!


Let Width = w
Let Length = w+7
w%2A%28w%2B7%29=260 Because l*w = A
w%5E2%2B7w-260=0
x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+
x+=+%28-7+%2B-+sqrt%28+7%5E2-4%2A1%2A-260+%29%29%2F%282%2A1%29+
x=%28-7%2B-sqrt%2849%2B1040%29%29%2F2
x=%28-7%2B-sqrt%281089%29%29%2F2
The square root of 1089 is 33. Because both dimensions must be positive,
x=%28-7%2B33%29%2F2
x=26%2F2
x=13
The width is 13cm and the length is 20cm.