Question

Solve 3x2 = -30x + 24. Using quadratic equation.

Answer 1

first set it equal to 0

3x^2+30x-24=0

Then use the quadratic formula! a b and c are the coefficients so
a=3, b=30 and c = -24

\[x=\frac{ -b \pm \sqrt{b^2-4ac} }{ 2a }\]

Answer 2

\[x ^{2} + 10x -8 = 0\]

\[\frac{ -10 \pm \sqrt{10^{2}+4*8} }{ 2 }\]

Answer 3

So
\[x = -5 \pm \sqrt{17}\]

Have I done that right?

Answer 4

I don't think so. I got \[-4\pm \sqrt{33}\] but thats not one of my answer choices..

Answer 5

It should be -5 not -4. Check you work.

http://www.wolframalpha.com/input/?i=3x2+%3D+-30x+%2B+24

Go to solutions.

Answer 6

Yeah, wow I messed up my arithmetic there.