Answer:
The measure of angle x is 40°
Explanation:
we know that
The measurement of the outer angle is the semi-difference of the arcs which comprises
see the attached figure with letters to better understand the problem
so
m∠x=(1/2)[arc AB-arc AC]
Find the measure of arc AC
we know that
arc AB+arc BC+arc AC=360° ----> by complete circle
substitute the given values
arc AB=200°
arc BC=40°
arc AC=?
200°+40°+arc AC=360°
240°+arc AC=360°
arc AC=360°-240°=120°
Find the measure of angle x
m∠x=(1/2)[200°-120°]=40°