Question

Given: BD is a diameter

m 1 = 100°
m BC= 30°

m 4 =

100
150
330

Answer 1

150

Explanation:

bc is along a straight line with section 4 straight lines are 180° if bc is 30° then 180°-30°=150°

Answer 2

The measure of ∠4 is 150°

Explanation:

Given the figure in which BD is the diameter of circle and

m∠1=100°

m(arc BC)=∠3=30°

we have to find the measure of ∠4.

As BD is a straight line as BD is diameter therefore

∠4 and ∠3 forms a linear pair

⇒ ∠4 and ∠3 are supplementary i.e these angles adds up to 180°

∠4 + ∠3 = 180°

∠4+30°=180°

∠4=180°-30°=150°

Hence, the measure of ∠4 is 150°