I think you would distribute what is in the parentheses and then make it so only a and b are on the left and i and the other characters that can be simplified are on the left but feel free to Google it.
Since 17 isnt a factor of 42 the only factor is 1
R * p = -37.8
Solve for either R or p.
R = -37.8/p
Now plug into R + p = 13.5
-37.8/p + p = 13.5
Solve for p.
After finding p, plug your p-value into either R + p or R*p to find R.
Take it from here.
When you buy a car you have all the money upfront ready either in cash, check, etc. Leasing is when you have a little bit or most of the money. Because you dont have all of it you pay for the car monthly and pay a little bit more than the actual value of the car as interest for "borrowing" their money since you couldn't afford the entire value of the car upfront. The more money you put down at the time of leasing, the less the interest usually is.