The general form of a quadratic equation is f(x)=ax2+bx+c
The standard form of a quadratic equation is f(x)=a(x-h)2+k, where (h,k) is the vertex of the parabola (maximum/minimum value)
"a" will be the same, but we need to find h and k. You can use a completing the square method to find the vertex, but the easiest way is to use the following formulas.
There is no real formula for k, but since (h,k) is a point on our graph, we can plug h into f(x) to get k.
Now, you have f(x)=-2x2+5x-8 this is in general form
For standard form
So we get, f(x)=-2(x-5/4)2-39/8
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