SOLUTION: how do you do a quadratic equation without a b value?

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Question 140566: how do you do a quadratic equation without a b value?
Found 2 solutions by oscargut, ptaylor:
Answer by oscargut(2103) About Me  (Show Source):
You can put this solution on YOUR website!
ax^2+c=0
then
ax^2=-c
then
x^2=-c/a
x=(+-)sqrt(-c/a)
example
3x^2-12=0
3x^2=12
x^2=4
x=2 or x=-2

Answer by ptaylor(2198) About Me  (Show Source):
You can put this solution on YOUR website!
how do you do a quadratic equation without a b value?

All quadratics have a b value but sometimes the b value is zero and, in fact, sometimes the c value or a a value is zero. If the a value is zero, I believe that it ceases to be a quadratic.
In other words:
Ax^2+C=0 can be written as:
Ax^2+0x+C=0 solve using the quadratic formula
x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+
x+=+%280+%2B-+sqrt%28+0-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+
x+=+%28%2B-+sqrt%28-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+
OK?

Hope this helps---ptaylor