Answer:
Angle MON is equal to 130 degrees.
Step-by-step explanation:
We are told LON is 180 degrees.
Angles LOM and MON are supplementary meaning they add to 180 degrees.
Using this information we know 12x+120=180.
We can use the subtractive property of equality to subtract 120 from both sides.
Do thins we get 12x=60.
Using the division property of equality we can divide both sides by 12 to get x=5.
We can then use the substitution property of equality to get MNO=8(5)+90.
We can then simplify to get MNO=130.
