Find the value of y so that line is passing through two points

What is the quadric regression equation that fits these data

Val and tony get paid per project. val is paid a project fee of $44 plus $12 per hour. tony is paid a project fee of $35 plus $15 per hour. write an expression to represent how much a company will pay to hire both to work the same number of hours on a project.

How are algebraic expressions evaluated using substitution?