y = 3x + 13
y = 7x + 17
Using the elimination method. Multiply both equations by common their common factors, 7 and 3. In order to cancel out the x variable.
7y = 21x + 91
3y = 21x + 51
Subtract the equation.
4y = 40
y=10
substitute 10 to either one of the equations to solve for x
10=3x+13
x=-1