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Kelas 8 Matematika
Bab Garis dan Sudut

12] 3a + 15° + 2a - 10° = 180°
5a + 5° = 180°
5a = 180° - 5°
a = 175°/5°
a = 35°

a + 8°
= 35° + 8°
= 43°

13] (9, 0) dan (0, 6)
m = (y2 - y1)/(x2 - x1)
m = (6 - 0)/(0 - 9)
m = 6/-9
m = -2/3