F(x) is the same as y.......so basically ur subbing in ur points into the equation to see if it comes out equal.
f(x) = 3 - 2x.....(-2,-1)....x = -2 and f(x) = -1
-1 = 3 - 2(-1)
-1 = 3 + 2
-1 = 5.....this is not true, so it is not a solution
and that is how to do this problem.....
(-1,5)......this IS a solution
(0,3)......this IS a solution
(1,0)...this IS NOT a solution
(2,-1)...this IS a solution
If you need further help on how they got the answer, this equation will take more time, but it will also help you understand these types of problems. Part÷Whole=Percent÷100
Part= X because it is what you are trying to find.
Whole=250 because it is what you are taking the percentage of.
Percent=80
Now you have:
X÷250=80÷100
Set this up in fraction form and cross multiply.
You get:
100x=250×80
250×80=20,000
100x=20,000
X=200
That is correct because it’s a real high school