Question

I need a little help understanding these?

Answer 1

When x = 2 then f(x) = 2^2 +2(2) -1 = 4 + 4 - 1 = 7
when x = 3 then f(x) = 3^2 +2(3) -1 = 9 + 6 - 1 = 14
when x = -3 then f(x) = (-3)^2 +2(-3) -1 = 9 - 6 - 1 = 2

(-3,2) (2, 7) and (3,14)

answer
Pairs
2    ------>   -3
14  ------>    3
7    ------>    2