Question 1137983: I'm at the beginning of college algebra, I have decent experience in algebra yet I have a hard time solving this among quadratic equations: 2(x+4)^2+18=0
Do I use the distributive property before using the quadratic formula? thanks in advance.
Found 3 solutions by josgarithmetic, Boreal, ikleyn:
Answer by josgarithmetic(39617)   (Show Source):
Answer by Boreal(15235)  (Show Source):
You can put this solution on YOUR website! This is vertex form, so the vertex is (-h, k), where h is the number in parentheses and k is the constant. If the vertex is (-4, 18), we know that the minimum is above the x-axis and any roots will be imaginary.
It is also part of completing the square, which we use to solve:
to solve
(x+4)^2=-9
x+4=+/- 3i,taking square root of both sides
x=-4+/-3i, are the two roots.
Answer by ikleyn(52781)  (Show Source):
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