SOLUTION: Which statement is true for the quadratic equation 0 = -2x^2 - 9x - 4? I have gotten to the point of -2x^2 - 9x 4 = 0, but I don't know what to do next. My answers are: A. The p

Algebra ->  Quadratic Equations and Parabolas  -> Quadratic Equations Lessons  -> Quadratic Equation Lesson -> SOLUTION: Which statement is true for the quadratic equation 0 = -2x^2 - 9x - 4? I have gotten to the point of -2x^2 - 9x 4 = 0, but I don't know what to do next. My answers are: A. The p      Log On


   

Question 66772: Which statement is true for the quadratic equation 0 = -2x^2 - 9x - 4?
I have gotten to the point of -2x^2 - 9x 4 = 0, but I don't know what to do next. My answers are: A. The product of the roots is 4/9
B. The product of the roots is -2.
C. The sum of the roots is 9/2.
D. The sum of the roots is -9/2
I do know that C is not a correct answer (my teacher told me so). THANKS
Oh, by the way I don't have a textbook pg. because our teacher just gave us the problems on paper.
Answer by Earlsdon(6294) About Me  (Show Source):
You can put this solution on YOUR website!
Let's solve the equation to find out what the roos are:
-2x%5E2-9x-4+=+0 Divide both sides by -1 to facilitate solving.
2x%5E2%2B9x%2B4+=+0 Factor the left side.
%282x%2B1%29%28x%2B4%29+=+0 Apply the zero product principle.
2x%2B1+=+0 and/or x%2B4+=+0
If 2x%2B1+=+0 then 2x+=+-1 and x+=+-1%2F2
If x%2B4+=+0 the x+=+-4
So the roots are:
x+=+-1%2F2 and x+=+-4
The product of these roots is: %28-1%2F2%29%28-4%29+=+2
The sum of these roots is: %28-1%2F2%29%2B%28-4%29+=+-9%2F2