SOLUTION: FACTOR THE TRINOMIAL COMPLETELY: x^2 + x-2 =

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Question 555661: FACTOR THE TRINOMIAL COMPLETELY: x^2 + x-2 =
Found 2 solutions by nerdybill, josmiceli:
Answer by nerdybill(7384) About Me  (Show Source):
You can put this solution on YOUR website!
x^2 + x-2
(x+2)(x-1)

Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
You can complete the square:
+x%5E2+%2B+x+-+2+=+0+
+x%5E2+%2B+x+=+2+
Take 1/2 of the coefficient of x,
square it, and add it to both sides
+x%5E2+%2B+x+%2B+%28+1%2F2+%29%5E2+=+2+%2B+%28+1%2F2+%29%5E2+
+x%5E2+%2B+x+%2B+1%2F4+=+2+%2B+1%2F4+
+%28+x+%2B+1%2F2%29%5E2+=+9%2F4+
+x+%2B+1%2F2+=+3%2F2+
(1) +x+=+1+
and, also
+x+%2B+1%2F2+=+-3%2F2+
(2) +x+=+-2+
Rewrite (1) and (2) as
(1) +x+-+1+=+0+
(2) +x+%2B+2+=+0+
The factors are:
+%28+x+-+1+%29+%2A+%28+x+%2B+2+%29+=+x%5E2+%2B+x+-+2+