SOLUTION: x2 +8x -84 =0

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Question 6035: x2 +8x -84 =0
Found 2 solutions by Abbey, CharStar:
Answer by Abbey(339) About Me  (Show Source):
You can put this solution on YOUR website!
If you can't figure out that this factors into:
(x+14)(x-6) then it is easy to use the quadratic equation:
Let a=1
Let b=8
Let c= -84
and use the quadratic equation:
x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+
x+=+%28-8+%2B-+sqrt%28+8%5E2-4%2A1%2A-84+%29%29%2F%282%2A1%29+
x+=+%28-8+%2B-+sqrt%28+64%2B336+%29%29%2F%282%29+
x+=+%28-8+%2B-+sqrt%28+400+%29%29%2F%282%29+
x+=+%28-8+%2B-+20%2F%282%29%29+
x+=+-4+%2B-+10+
x=-14, x=6

Answer by CharStar(110) About Me  (Show Source):
You can put this solution on YOUR website!
(X+14)(X-6)= 0
(X+14)= 0
(X-6)=0
X=-14
X=+6
Check your answer
x2 -6x + 14x - 84 = 0
x2+8x-84=0