SOLUTION: solve using the quadratic formula {{{x^2-4x-7=0}}}

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Question 36751: solve using the quadratic formula
x%5E2-4x-7=0
Answer by Cintchr(481) About Me  (Show Source):
You can put this solution on YOUR website!
+x%5E2-4x-7=0+
+x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+
a=1
b=-4
c=-7
+x+=+%28-%28-4%29+%2B-+sqrt%28+%28-4%29%5E2-4%2A1%2A-7+%29%29%2F%282%2A1%29+
+x+=+%28%284%29+%2B-+sqrt%28%28-4%29%5E2-4%2A1%2A-7+%29%29%2F%28%282%2A1%29%29+
+x+=+%28%284%29+%2B-+sqrt%28%2816-4%2A1%2A-7+%29%29%29%2F%282%2A1%29+
+x+=+%28%284%29+%2B-+sqrt%28%2816%2B28+%29%29%29%2F%282%2A1%29+
+x+=+%28%284%29+%2B-+sqrt%28%2844+%29%29%29%2F%282%2A1%29+
+x+=+%28%284%29+%2B-+sqrt%28%2844+%29%29%29%2F%282%29+
root out 44
+x+=+%28%284%29+%2B-+2sqrt%28%2811+%29%29%29%2F%282%29+
Reduce the fraction
+x+=+%282%29+%2B-+sqrt%28%2811+%29%29+