Answer:
D)15; 100°.
Explanation:
Given : Verticle opposite angles (6a + 10) and (3a + 55).
To find : Find the value of a. b. Find the value of the marked angles.
Solution : We have given (6a + 10) and (3a + 55).
Verticle opposite angles are equal
Then
6a + 10 = 3a + 55
On subtracting both sides by 3a
6a - 3a + 10 = 55
3a + 10 = 55
On subtracting by 10 both sides.
3a = 55 -10.
3a = 45.
On dividing the 3 by both sides
a = 15°.
Then ,
6 (15) + 10.
90 + 10 = 100
b =100°.
Therefore, D)15; 100°.