Answer:
30
Step-by-step explanation:
The angle next to the 100 degree (deg) one is supplemental (makes 180 deg with) to the 100 deg one. since the ray where the 100 deg and that angle are located is a straight line (180 deg).
We can find that mystery angle by subtracting that 100 from the 180, getting us 80 deg.
Now according to Geometry, the angles of a triangles must add up TO 180, so we can set up an equation with all of our known values to find x:
70 + 80 + x = 180
150 + x = 180 (combine like terms)
x = 30 (subtract 150 both sides)
lmk if u got any Qs
:-)
