Answer:
34
Step-by-step explanation:
We know the straight line is equal to 180°, and the three angles that make it are (x+12),100°, and x. We can use the equation 180=(x+12)+100+x to find x.
180=(x+12)+100+x
We can remove the parentheses and combine x plus x to 2x.
180=100+2x+12
100+12=112
so
180=112+2x
-112 -112
68=2x
÷2 ÷2
34=x
