Answer:
C is a function... all the others are not functions since it doesn't pass the line test.
Step-by-step explanation:
Took me a minute to think.
Form ratios.
x, the small triangle, forms a ratio with 6, the big triangle.
The part of the side that is equal(with the dash) that is part of the small triangle
is equal to 6-x, the big triangle.
Yes, you can cross-multiply here!

<em>Now,</em><em> </em>cross multiply.
P.S. Use distributive property.
36-6x = 8x
Add 6x on both sides.
36=14x
Divide by 14 on both sides.
x =

=
Given: p=2, h=8
5p^2=h
5(2)^2=8 ------- substitution here
5(4)=8
20 doesn't equal 8
I did exponents first because it comes before multiplication in the order of opertions.