SOLUTION: A rectangular frame measures 4o inches across its diagonal. If the width is 8 inches less than the the length find the frame

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Question 528709: A rectangular frame measures 4o inches across its diagonal. If the width is 8 inches less than the the length find the frame
Found 2 solutions by mathstutor494, KMST:
Answer by mathstutor494(120) About Me  (Show Source):
You can put this solution on YOUR website!
length of the frame : 32 inch

Answer by KMST(5328) About Me  (Show Source):
You can put this solution on YOUR website!
The way to get at the solution of this problem is to combine algebra with Pythagoras' theorem.
The length (L) and width (W) and diagonal of the frame form a right triangle, so Pythagoras says that
L%5E2%2BW%5E2=40%5E2
In algebra language, "the width is 8 inches less than the the length" translates as
W=L-8
Substituting you get
L%5E2%2B%28L-8%29%5E2=40%5E2
and you can work that into a quadratic equation.
The equation will have two solutions, but you cannot use the negative solution, because frame lengths are always measured as positive numbers.