Answer:
x = 6
75 degrees
Explanation:
Since these are two parallel lines cut by a transversal, the angles are the same. Therefore,
11x + 9 = 12x + 3
subtract 11x from both sides
9 = x + 3
subtract 3 from both sides
6 = x
for the angles, just plug in the numbers
11(6) + 9 = 66 + 9 = 75
12(6) + 3 = 72 + 33 = 75