Which equation represents a function?

How can you find the conditional probability of a given b as the fraction of b’s outcomes that also belong to a, and interpret the answer in terms of the model? i just need a good explanation

Part a : solve -vp + 40 < 65 for v part b : solve 7w - 3r = 15 for r show your work .

What are the solutions of the system? solve by graphing. y = x^2 + 3x + 2 y = 2x + 2