SOLUTION: 120 less than the square of a number is the same as twice the number

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Question 838535: 120 less than the square of a number is the same as twice the number
Answer by LinnW(1048) About Me  (Show Source):
You can put this solution on YOUR website!
120 less than the square of a number is the same as twice the number
-120+%2B+x%5E2+=+2x+
add -2x to each side
+x%5E2+-2x+-120++=+0+
We can factor
+%28x+-+12%29%28x+%2B+10%29+=+0+
Possible values for x are 12 and -10
For 12 , -120+%2B+%2812%29%5E2+=+2%2812%29
-120+%2B+144+=+24
This looks good so 12 works.