Jawabanmu

2014-09-12T00:04:31+07:00
ax + by - 5 = 0
ax + by = 5
(2,1) & (5,5)
(y-y₁)/y₂-y₁ = (x-x₁)/x₂-x₁)
y-1/5-1 = x-2/5-2
y-1/4 = x-2/3
3y - 3 = 4x -8
4x - 3y = 5
Jadi, a= 4 dan b = -3
(4)(-3)² = 144