SOLUTION: Solve by completing the square: x^2+5x-50=0

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Question 1127304: Solve by completing the square: x^2+5x-50=0
Answer by math_helper(2461) About Me  (Show Source):
You can put this solution on YOUR website!
+x%5E2+%2B+5x+-+50+=+0+
+x%5E2+%2B+5x+%2B+%2825%2F4%29+-+50+=+25%2F4+
+x%5E2+%2B+5x+%2B+%2825%2F4%29++=+25%2F4+%2B+50+
+%28x+%2B+5%2F2%29%5E2+=+225%2F4+
++%28x%2B5%2F2%29+=+%2B-+15%2F2+ <— introduce +/- after sqrt of both sides
++x+=+-5%2F2+%2B-+15%2F2++
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Ans: +highlight%28+x+=+5+%29+ and +highlight%28+x+=+-10%29+ are the two solutions
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Check:
x=5: 5^2 + 5(5) - 50 = 25+25-50 = 0 (ok)
x=-10: (-10)^2 + 5(-10) - 50 = 100 - 50 - 50 = 0 (ok)