SOLUTION: If the length of a rectangle is 3 feet longer than the width and the diagonal is 5 feet, then what are the length and width?
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-> SOLUTION: If the length of a rectangle is 3 feet longer than the width and the diagonal is 5 feet, then what are the length and width?
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You can put this solution on YOUR website! If the length of a rectangle is 3 feet longer than the width and the diagonal
is 5 feet, then what are the length and width?
:
Using a^2 + b^2 = c^2
where
let x = width (a)
then
(x+3) = the length (b)
and
c = 5
:
x^2 + (x+3)^2 = 5^2
FOIL
x^2 + x^2 + 6x + 9 = 25
;
2x^2 + 6x = 9 - 25 = 0
:
2x^2 + 6x - 16 = 0
Simplify, divide by 2
x^2 + 3x - 8 = 0
Use the quadratic formula to find x
in this problem: a=1; b=3; c=8
:
Do the math and you should get a positive solution: x=1.7 is the width
and
4.7 is the length
;
;
Check on a calc enter = 4.998 ~ 5
