SOLUTION: f(x)=-3x^2 make a table and a graph

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Question 213428: f(x)=-3x^2 make a table and a graph
Answer by drj(1380) About Me  (Show Source):
You can put this solution on YOUR website!
f(x)=-3x^2 make a table and a graph

Here's the list of points:
x......y=-3x^2
-5 -75
-4 -48
-3 -27
-2 -12
-1 -3
0 0
1 3
2 12
3 27
4 48
5 75

Here's the graph:

Solved by pluggable solver: SOLVE quadratic equation with variable
Quadratic equation ax%5E2%2Bbx%2Bc=0 (in our case -3x%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%2A-3%2A0=0.

Discriminant d=0 is zero! That means that there is only one solution: x+=+%28-%280%29%29%2F2%5C-3.
Expression can be factored: -3x%5E2%2B0x%2B0+=+-3%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+-3%2Ax%5E2%2B0%2Ax%2B0+%29



Note: The vertex is (0,0)

I hope the above steps were helpful.

And good luck in your studies!

For free Step-By-Step Videos on Introduction to Algebra, please visit http://www.FreedomUniversity.TV/courses/IntroAlgebra or for Trigonometry visit http://www.FreedomUniversity.TV/courses/Trigonometry.

Respectfully,
Dr J