SOLUTION: I don't understand how to use the formula of ax^+bx+c=0 My problem is this x^2+7x=180 I need x answered

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Question 220887: I don't understand how to use the formula of ax^+bx+c=0
My problem is this x^2+7x=180
I need x answered
Found 2 solutions by edjones, josmiceli:
Answer by edjones(8007) About Me  (Show Source):
You can put this solution on YOUR website!
x^2+7x=180
x^2+7x-180=0
a=1, b=7, c=-180
.
Ed
.
Solved by pluggable solver: SOLVE quadratic equation with variable
Quadratic equation ax%5E2%2Bbx%2Bc=0 (in our case 1x%5E2%2B7x%2B-180+=+0) has the following solutons:

x%5B12%5D+=+%28b%2B-sqrt%28+b%5E2-4ac+%29%29%2F2%5Ca

For these solutions to exist, the discriminant b%5E2-4ac should not be a negative number.

First, we need to compute the discriminant b%5E2-4ac: b%5E2-4ac=%287%29%5E2-4%2A1%2A-180=769.

Discriminant d=769 is greater than zero. That means that there are two solutions: +x%5B12%5D+=+%28-7%2B-sqrt%28+769+%29%29%2F2%5Ca.

x%5B1%5D+=+%28-%287%29%2Bsqrt%28+769+%29%29%2F2%5C1+=+10.365424623862
x%5B2%5D+=+%28-%287%29-sqrt%28+769+%29%29%2F2%5C1+=+-17.365424623862

Quadratic expression 1x%5E2%2B7x%2B-180 can be factored:
1x%5E2%2B7x%2B-180+=+1%28x-10.365424623862%29%2A%28x--17.365424623862%29
Again, the answer is: 10.365424623862, -17.365424623862. Here's your graph:
graph%28+500%2C+500%2C+-10%2C+10%2C+-20%2C+20%2C+1%2Ax%5E2%2B7%2Ax%2B-180+%29

Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
The equation is called quadratic, or 2nd degree.
When you plot it on a graph, it's called a parabola.
It's in the form ax%5E2+%2B+bx+%2B+c+=+0, but first
subtract 180 from both sides, and it will be in
that form
x%5E2+%2B+7x+-+180+=+0
Matching it up with the general equation,
a+=+1
b+=+7
c+=+-180
Now use the quadratic formula to solve
x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+
x+=+%28-7+%2B-+sqrt%28+7%5E2-4%2A1%2A%28-180%29+%29%29%2F%282%2A1%29+
x+=+%28-7+%2B-+sqrt%28+49+%2B+720+%29%29%2F%282%2A1%29+
x+=+%28-7+%2B-+sqrt%28+769+%29%29%2F2+
769 isn't a perfect square- are you sure you
copied this right?