Question

What is the equation of the graph?

Answer 1

We have points (-1,3),(0,1),(1,3) so we can set up a system of equations for the general form ax^2+bx+c...

a+b+c=3, 0a+0b+c=1, a-b+c=3  getting differences

a+b=2, -a+b=-2  getting the sum

2b=0, b=0, making a+b=2 become:

a+0=2, a=2, making a+b+c=3 become:

2+0+c=3, c=1 so

y=2x^2+1