SOLUTION: What's the next step in solving the equation x^2+14x-4=30 after you add 4 to each side?

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Question 846047: What's the next step in solving the equation
x^2+14x-4=30
after you add 4 to each side?

Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!
 
Hi,
The MTEL is solving by completing the Square:
x^2+14x-4=30
x^2+14x = 34
+highlight_green%28x%5E2+%2B+14x+%2B+49+%29= 34 + 49 |Adding 49 to each side yeilds a perfect square on the left
(x+7)^2 = 83 |Taking the square root of both sides of EQ
x+7 = ± sqrt(83)
x = -7 ± sqrt(83)
Answers the same..just a different method of finding the Solution for x
Set to zero first (solving Using the Quadratic Formula)
The factor theorem states that a polynomial f(x) has a factor (x − k) if and only if f(k) = 0
x^2 + 14x - 34 = 0 use Quadratic formula
x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+
x+=+%28-14+%2B-+sqrt%28332%29%29%2F%282%29+
x+=+%28-14+%2B-+sqrt%284%2A83%29%29%2F%282%29+
x+=+%28-14+%2B-+2sqrt%2883%29%29%2F%282%29+
x+=+-7+%2B-+sqrt%2883%29+