SOLUTION: Please Help Me Solve This Word Problem: the length of a rectangle is 8 inches greater than its width. find the width of the rectangle if its area is 105 square inches. ?

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Question 423020: Please Help Me Solve This Word Problem: the length of a rectangle is 8 inches greater than its width. find the width of the rectangle if its area is 105 square inches. ?
Answer by Gogonati(855) About Me  (Show Source):
You can put this solution on YOUR website!
Solution: Denote x inches the width. Than its length is: x+8 inches.
Since its area is105 square inches we write the equation:
x*(x+8)=105 => x%5E2%2B8x=105 => x%5E2%2B8x-105=0
The final equation is a quadratic equation. Use the quadratic formula to solve it.
x=%28-8%2B-sqrt%288%5E2-4%2A%281%29%2A%28-105%29%29%2F%282%2A1%29%29
The root of the equation is x=7.
Answer: the width is 7 inches and the length is 7+8=15 inches.