tolong jawab dengan cara y...

7. 15x -6 + 8x + 4 = 90°
23x - 2 = 90°
23x = 90° + 2
23x = 92°
x = 92 ÷ 23 = 4°
ADB = 15x -6 = 15(4) - 6 = 60° - 6 = 54° Opsi C