What value of b will make the system y=5x+9 & y=25x+b intersect at point (10,9)

Can you tell me the answer and if you can tell me how to do it?

When the two equations intersect, y=5x+9 and y=25x+b are equal i.e. 5x+9=25x+b.
Since the point of intersection is (10,9), set x=10.
5(10)+9=25(10)+b
59=250+b
b=191