SOLUTION: Why does a quadratic equation have two answers?

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Question 936660: Why does a quadratic equation have two answers?
Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!
Why does a quadratic equation have two answers?
y = ax^2 + bx + c
x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+
Actually, it doesn't always...
only if sqrt%28+b%5E2-4%2Aa%2Ac+%29 > 0 does it have two 'real' answers... (Blue)
sqrt%28+b%5E2-4%2Aa%2Ac+%29 = 0 , one answer. Ex: y = x^2 (Green)
sqrt%28+b%5E2-4%2Aa%2Ac+%29 = 0, Imaginary roots only, does not cross x-axis (Purple)
...
x^2(green),(x-1)^2 -1(Blue), (x-1)^2 +3 (Purple)
graphically a quadratic equation is a Parabola:
generally, it will cross the x-axis twice...but not always...