SOLUTION: Please help.me .solve this equation . x² -2x -13 = 0

Algebra ->  Quadratic Equations and Parabolas -> SOLUTION: Please help.me .solve this equation . x² -2x -13 = 0       Log On


   

Question 607524: Please help.me .solve this equation . x² -2x -13 = 0
Answer by alicealc(293) About Me  (Show Source):
You can put this solution on YOUR website!
x%5E2-2x-13=0
Because we can't factorize this, use the formula:
x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+
a = 1, b = -2, c = -13
x+=+%28-%28-2%29+%2B-+sqrt%28+%28-2%29%5E2-4%2A1%2A%28-13%29+%29%29%2F%282%2A1%29+
x+=+%282+%2B-+sqrt%28+4%2B52+%29%29%2F2+
x+=+%282+%2B-+sqrt%28+56+%29%29%2F2+
x+=+%282+%2B-+sqrt%28+4%2A14+%29%29%2F2+
x+=+%282+%2B-+2sqrt%28+14+%29%29%2F2+
x+=+1+%2B-+sqrt%28+14+%29+
x+=+1+%2B+sqrt%28+14+%29+ or x+=+1+-+sqrt%28+14+%29+