PLEASE HELP WILL GIVE 15 POINTS AND GOOD RATINGS

Determine whether each relation is a function. Explain.

{(1, 12), (4, 18), (7, 22), (10, 28)}

a.
yes; Each element of the domain is paired with exactly one element of the range.

b.
yes; Each element of the range is paired with exactly one element of the range.

c.
no; Some values of the domain are paired with more than one value of the range.

d.
no; Some values of the range are paired with more than one value of the domain.

First locate the turning point (vertex) of the graph. which is at the coordinates x=5 and y=9 or (5; 9).to determine whether it's a maximum or mininum value, you have to discern whether the vertex's y-value is the highest value or lowest value the graph can reach. since the vertex's y-value, 9 is the highest value the graph can reach, it will be a maximum.another basic way to determine whether the vertex's value is max or min is to see if the graph is smiling or sad. if it's smiling, the turning point/vertex would be a minimum, while a sad parabola would have a maximum y-value at the vertex.