The Slope of EF is -3/2 Which segments are perpendicular to EF?

How do you determine whether a relationship represented as as graph is linear or nonlinear

Given the two similar triangles, how do i find the missing length? if a=4, b=5, and b'=7.5 find a'

In a small section of a stadium there are 40 spectators watching a game between the cook islands and fiji. they all support at least one of the two teams. 25 spectators support the cook islands and 16 of these support both teams. how many support only fiji?