Himpunan penyelesaian dari sistem.persamaan ax-by=-1 dan 3/2ax-5by=16 adalah {(-3,-5)}. Nilai a+b adalah

Hp = {(-3, -5)}
a + b = ...
Pers 1: ax - by = -1
-3a - (-5)b = -1
-3a + 5b = -1
Pers 2: 3/2ax - by = 16
3/2 (-3)a - (-5)b = 16
-9/2a + 5b = 16
Eliminasi
-3a + 5b = -1
-9/2a + 5b = 16
3/2a = 16
a = 32/3
Substitusi
-3a + 5b = -1
-3(32/3) + 5b = -1
-32 + 5b = -1
5b = -1 + 32
5b = 31
b = 31/5
a + b = 32/3 + 31/5
= (160 + 93)/15
= 253 / 15