SOLUTION: Please Help. I have a textbook and it takes me through the steps on what I need to do, but I still do not understand exactly why I need to do all these steps. My problem does not c

Algebra ->  Quadratic Equations and Parabolas  -> Quadratic Equations Lessons  -> Quadratic Equation Lesson -> SOLUTION: Please Help. I have a textbook and it takes me through the steps on what I need to do, but I still do not understand exactly why I need to do all these steps. My problem does not c      Log On


   

Question 105812: Please Help. I have a textbook and it takes me through the steps on what I need to do, but I still do not understand exactly why I need to do all these steps. My problem does not come from a textbook that I know of. I only havce the text for guidance. This is my problem: solve quadratic equation by using quadratic formula. x^2-x-6=0 This is what I have done so far, but I know it is not correct. x^2-x-6+6=0+6 x^2-x=6 x=6 If you could help I would greatly appreciate it. And I thank you for your time.
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
x%5E2-x-6=0
The quadratic formula gives you a formula to solve the equation,
ax%5E2%2Bbx%2Bc=0
by using
x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+
Your equation is already in the form needed to used the quadratic formula.
You just need to match a,b, and c terms between your equation and the example and plug those values in the formula.
For the a term,
highlight%28ax%5E2%29%2Bbx%2Bc=highlight%28x%5E2%29-x-6
ax%5E2=x%5E2
a=1
Do the same for b anc c and then use the quadratic formula to solve for the roots. Watch your negative signs too.
x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2A1%2Ac+%29%29%2F%282%2A1%29+
If you get stuck again, post another question.