By what percent will the product of two numbers decrease if one of them is increased by 20% and the other is decreased by 20%?

HELP ME PLEASE I HAVE A HOMEWORK ASSIGNMENT DUE

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

Solve the problem by making up an equation. a man could arrive on time for an appointment if he drove the car at 40 mph; however, since he left the house 15 minutes late, he drove the car at 50 mph and arrive 3 minutes early for the appointment. how far from his house was his appointment?

Sally deposited money into a savings account paying 4% simple interest per year.the first year,she earn $75 in interest.how much interest will she earn during the following year?