bantu no 24 ya kak.aku lupa cara cepatnya

Bab Garis dan Sudut
Matematika SMP Kelas VII

5x - 40° = 50° + 2x
5x - 2x = 50° + 40°
3x = 90°
x = 90° : 3
x = 30°

sudut ABC
= 180° - (5x - 40°)
= 180° - (5 . 30° - 40°)
= 180° - (150° - 40°)
= 180° - 110°
= 70°

◎◎ C ◎◎