The missing angle would be 68 because the the triangles can be alternate exterior
ANSWER
y = 2/3x + 15
Explanation:
Equation used: y - y1 = m( x - x1 )
y - 9 = 2/3 ( x - -9 )
y - 9 = 2/3x + 6 ( distribution )
y - 9 = 2/3x + 6 ( add 9 to 6 )
y = 2/3x + 15
I hope this helps, i got it from a cheat sheet online