Ido not understand how to do this problem

What is the solution to this system of equations? y= 2x - 3.5 x - 2y = -14

Cherie works in retail and her weekly salary includes commission for the amount she sells. the equation s=400+0.15c models the relation between her weekly salary, s, in dollars and the amount of her sales, c, in dollars. interpret the slope of the equation.

The tree filled 3/4 of a cup in 1/2 and hour at what rate does syurup flow from the tree