Algebra
# Linear Equations

The point $(12, k)$ lies on the line $y = 2x + 7$. What is the value of $k$?

If $P=(a, 3)$ is a point on the line $x+y-11=0,$ what is the value of $a$?

If $P=(5, a)$ is a point on the line $3x+y-22=0,$ what is the value of $a$?