Answer ASAP!! Exponential models

The sum of two numbers is 86, and their difference is 20. find the two numbers

Omar is going on a road trip! the car rental company offers him two types of cars. each car has a fixed price, but he also needs to consider the cost of fuel. the first car costs $90 to rent, and because of its fuel consumption rate, there's an additional cost of s0.50 per kilometer driven.

Sara made $253 for 11 hours of work. at the same rate how much would he make for 7 hours of work?