Answer:
1. 51°
2. 55°
3. 5x + 10
Explanation:
1. We know ∠B + 39° = 90°, so ∠B = 90 - 39 = 51
2. We can use an algebraic equation to solve this problem.
2x + 70 = 180
2x + 70 (-70) = 180 (-70)
2x (/2) = 110 (/2)
x = 55
3. ∠ABD = (3x + 10) + (2x) = 5x + 10