Answer:
- 12. x = 5, m∠1 = 13°
- 13. a = 9°
Step-by-step explanation:
12..................................
Given:
- m∠1 = (2x + 3)
- m∠3 = (6x - 17)
- x? m∠1?
Solution:
∠1 and ∠3 are vertical angles.
We know the property that vertical angles are equal:
- 2x + 3 = 6x - 17
- 6x - 2x = 3 + 17
- 4x = 20
- x = 5
- m∠1 = 2*5 + 3 = 13°
13 ..................................
Given
- m ∠ 2 = (15a + 8)
- m ∠ 3 = (5a - 8)
- a = ?
Solution
∠2 and ∠3 are supplementary angles.
We know the property that supplementary angles add up to 180°:
- 15a + 8 + 5a - 8 = 180°
- 20a = 180°
- a = 180°/20
- a = 9°