SOLUTION: find the length of the diagonal of a square in which the diagonal is 4 units longer than the length of a side.

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Question 205593: find the length of the diagonal of a square in which the diagonal is 4 units longer than the length of a side.
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
find the length of the diagonal of a square in which the diagonal is 4 units longer than the length of a side.
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Draw the picture of a square.
Label the sides as "x".
Label the diagonal as "x+4".
Use Pythagoras to solve for "x":
x^2 + x^2 = (x+4)^2
2x ^2 = x^2 + 2x + 16
x^2 - 2x - 16 = 0
Use the quadratic formula to get:
x = [2 +- sqrt(4 - 4*1*-16)]/2
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x = [2 +- sqrt(4+64)]/2
x = [2 +- sqrt(68)]/2
Positive Solution:
x = [2 + sqrt(68)]/2
x = 5.123 units
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Cheers,
Stan H.