Answers:
It's basically Inside, Outside, Outside, Inside. (I. O.O.I.)
Explanations:
Given
[tex]f(x)=-(x-3)(x+1)[/tex]
Distribute the (-1) to (x-3)
[tex]f(x)=(-x+3)(x+1)[/tex]
Now let's work the I. O. O. I.
Inside:
[tex](-x)(x)=-x^2[/tex]
Outside:
[tex](-x)(1)=-x[/tex]
Outside:
[tex](3)(x)=3x[/tex]
Inside:
[tex](3)(1)=3[/tex]
Add both the outsides (-x) and (3x) together
[tex]-x+3x=2x[/tex]
Your new equations is now.
[tex]f(x)=-x^2+2x-3[/tex]
