The quotient of four times a number and nine in an algebraic expression

Find the constant of variation for the relation and use it to write an equation for the statement. then solve the equation.

Lena reflected this figure across the x-axis. she writes the vertices of the image as a'(−2, 8), b'(−5, 6), c'(−8, 8), d'(−4, 2).

According to the general equation for conditional probability if p(anb)=3/7 and p(b)=7/8 what is p(a i b)