If the line passing through point (a,1) and (8,7) is parallel to the line passing through the points (4,9) and (a+2,1) what is the value of a?
since the slopes are the same,
6/(8-a) = -8/(a-2)
6a-12 = 8a-64
2a = 52
a = 26
6/(8-a) = -8/(a-2)
6a-12 = 8a-64
2a = 52
a = 26