## gfields444 Group Title Solve. 2x2 + 13x = –20 2 years ago 2 years ago

1. mathslover

ok lemme give you a brief intro. to quadratic equation : $\large{ax^2+bx+c=0}$ -> general form of a quadratic equation

2. mathslover

what do you think is the above equation , a quadratic equation?

3. gfields444

Yes

4. mathslover

ok good , so remember that the roots of a quadratic equation are : $\large{roots =\frac{-b\pm \sqrt{b^2-4ac}}{2a}}$

5. mathslover

put b = 13 , a = 2 and c = 20

6. gfields444

I'm not sure

7. mathslover

ok .. see solve this now : $\large{\frac{-13\pm \sqrt{169-160}}{4}}$ $\large{\frac{-13\pm \sqrt{9}}{4}}$

8. gfields444

x= 1/3 and x=3?

9. mathslover

-10/4 = -5/2 and -16/4 = -4

10. mathslover

sqrt{9}=3

11. gfields444

Ohhh. Wait okay I see what I did wrong. Thank you!