3. Substitute 5 for x and solve for y.
3x - 6y = 9 , x = 5
3(5) - 6y = 9
15 - 6y = 9
-6y = -6
4. Check the solution in both original equations.
3x - 6y = 9 , x = 5 and y = 1
3(5) - 6(1) = 9
15 - 6 = 9
9 = 9 ---> True
Therefore, the solution of the equation is (5, 1)
the graph of x = 5 is a vertical line along x = 5. The two line if graph together they will intersect when x = 5 and y = 1.
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Happy graphing