SOLUTION: Use the quadratic formula to determine the x-intercepts (if any) of the following function. Then evaluate the function for several values of x, and use the resulting points to grap

Algebra ->  Quadratic Equations and Parabolas -> SOLUTION: Use the quadratic formula to determine the x-intercepts (if any) of the following function. Then evaluate the function for several values of x, and use the resulting points to grap      Log On


   

Question 337831: Use the quadratic formula to determine the x-intercepts (if any) of the following function. Then evaluate the function for several values of x, and use the resulting points to graph the function.
f(x)= 2x^2
I got one(I think).
2x^2= 0
divide each side by 2
2x^2/2= 0/2
x^2= 0
x= 0
Am I doing this correctly? I need to plot several points.
Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
Use the quadratic formula to determine the x-intercepts (if any) of the following function. Then evaluate the function for several values of x, and use the resulting points to graph the function.
f(x)= 2x^2
I got one(I think).
2x^2= 0
divide each side by 2
2x^2/2= 0/2
x^2= 0
x= 0
----------
That's correct, but you didn't use the quadratic formula.
Solved by pluggable solver: SOLVE quadratic equation (work shown, graph etc)
Quadratic equation ax%5E2%2Bbx%2Bc=0 (in our case 2x%5E2%2B0x%2B0+=+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=%280%29%5E2-4%2A2%2A0=0.

Discriminant d=0 is zero! That means that there is only one solution: x+=+%28-%280%29%29%2F2%5C2.
Expression can be factored: 2x%5E2%2B0x%2B0+=+%28x-0%29%2A%28x-0%29

Again, the answer is: 0, 0. Here's your graph:
graph%28+500%2C+500%2C+-10%2C+10%2C+-20%2C+20%2C+2%2Ax%5E2%2B0%2Ax%2B0+%29

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