What is the y-intercept of the line that passes through (-1,-5) and (-3,-7)?

Country carpets charges $22 per square yard for carpeting, and an additional installation fee of $100. city carpets charges $25 per square yard for the same carpeting, and an additional installation fee of $70

Can someone explain to me how to do

5. (04.07)which of the following exponential functions goes through the points (1, 12) and (2, 36)? (2 points)f(x) = 3(4)^xf(x) = 4(3)^-xf(x) = 3(4)^-xf(x) = 4(3)^x