SOLUTION: What is the answer to negative B plus a minus of square root of B squared square- 4AC over 2A

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Question 1029499: What is the answer to negative B plus a minus of square root of B squared square- 4AC over 2A
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
That is called the quadratic formula. Here it is:
+x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+
Because of the + and - before the square root sign,
you get two x's, you can call them +x%5B1%5D+ and +x%5B2%5D+
They are the roots of the quadratic
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You get the a, b, and c from the general form of the quadratic:
+a%2Ax%5E2+%2B+b%2Ax+%2B+c+=+0+
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Here's an example, and it's plot:
+f%28x%29+=+x%5E2+%2B+x+%2B+1%2F4+
Set +f%28x%29+=+0+ to get roots:
+x%5E2+%2B+x+%2B+1%2F4+=+0+
+a+=+1+
+b+=+1+
+c+=+1%2F4+
Plot:
+graph%28+400%2C+400%2C+-4%2C+4%2C+-10%2C+10%2C+x%5E2+%2B+x+%2B+1%2F4+%29+
Note that there is just 1 root ( where the curve touches the x-axis )
This is because +b%5E2+=+4%2Aa%2Ac+