Please help me with this question. I don't think I understand it. Quadratic functions graphing #15-19. Will pick brainliest answer, thank you :)

15) (1, 1) and (-1, 1)

16) (1, 2) and (-1, 2)

17 (1,1/2) and (-1, 1/2)

18) (1,1/4) and (-1, 1/4)

19) 16 is vertical stretch, 17 and 18 is vertical compressed

Step-by-step explanation:

for qs 15-18 since x is 1 or -1 if you sq 1 or -1 you will always get 1

so y is the "a" value in the equation  y=ax²

for qs 19

y=ax²

so if a>1 -- then vertical stretch

when 0<a<1 -- then vertical compressed