SOLUTION: The length of a rectangle is 2 m less than the diagonal and the width is 8 m less than the diagonal. If the area is 75 m2, how long is the diagonal? Round your answer to the neare

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Question 887147: The length of a rectangle is 2 m less than the diagonal and the width is 8 m less than the diagonal. If the area is 75 m2, how long is the diagonal? Round your answer to the nearest tenth.
Answer by lwsshak3(11628) About Me  (Show Source):
You can put this solution on YOUR website!
The length of a rectangle is 2 m less than the diagonal and the width is 8 m less than the diagonal. If the area is 75 m2, how long is the diagonal? Round your answer to the nearest tenth.
***
let x=length of diagonal
x-2=length of rectangle
x-8=width of rectangle
..
area of rectangle=length*width
(x-2)(x-8)=75
x^2-10x+16=75
x^2-10x-59=0
solve for x by quadratic formula:
x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+
a=1, b=-10, c=-59
ans:
x=-4.2 (reject)
or
x=14.2
length of diagonal=14.2 m