Answer:
x = 26
Explanation:
Supplementary angles mean that when the two angles are added together, they add up to 180. With this info, we can set the two expressions equal to 180
124 + (2x + 4) = 180.
128 + 2x = 180 combine like terms
2x = 52 subtract both sides by 128
x = 26. divide both sides by 2