1. Indicate whether each set of points is a function or relation.
a) {(1,1), (2,2), (3,5),(3,7)}
e)
x² + y² = 9
b)
(-3,1),(3,1), (8,7), (9,-2), (11,6)}
c) (x,5) for all real x
d) (2, y) for all real y
f)_y=√16-x²
g) y=x+2
h) y=2-x²