SOLUTION: i cant got the answer to this question 2x^2-15+7.

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Question 583406: i cant got the answer to this question 2x^2-15+7.
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
Is the problem to find the roots?
+2x%5E2-15x+%2B7+=+0+
Complete the square
+2x%5E2-15x++=+-7+
+x%5E2+-+%2815%2F2%29%2Ax+=+-%287%2F2%29+
+x%5E2+-+%2815%2F2%29%2Ax+%2B+%2815%2F4%29%5E2+=+-%287%2F2%29+%2B+%2815%2F4%29%5E2+
+%28+x+-+15%2F4+%29%5E2+=+-%2856%2F16%29+%2B+225%2F16+

+x+=+28%2F4+
+x+=+7+
and also:
+x+-+15%2F4+=+-%2813%2F4%29+
+x+=+2%2F4+
+x+=+1%2F2+
Rewrite these as:
+x+-+7+=+0+
+x+-+1%2F2+=+0+
+%28+x+-+7+%29%2A%28+x+-+1%2F2+%29+=+0+
+%28+x+-+7+%29%2A%28+x+-+1%2F2+%29+=+x%5E2+-+7x+-+%281%2F2%29%2Ax+%2B+7%2F2+ answer
+x%5E2+-+%2815%2F2%29%2Ax+%2B+7%2F2+=+0+
Multiply both sides by 2
+2x%5E2+-+15x+%2B+7+=+0+
So, the factors are correct