Help plz i will give brainlest to the right person

Solve the system of equations y= 3/2 - 1, -x+ y =-3

Acomputer store bought a program at a cost of $10 and sold it for $13. find the percent markup

Sam is a waiter at a local restaurant where he earns wages of $5 per hour sam figures that he also eams about $3 in tips for each person he serves sam works 6 hours on a particular day. if n represents the number of people sam serves that day, which of the following functions could sam use to figure ehis total earings for the do o a. en) = 30 o b. en) = 5n+ 18