Minta tolong Nya ples cara Nya

p = x + 2y - 6
p = (y - 2x + 25) : 2
p = p
2(x + 2y - 6) = y - 2x + 25
2x + 4y - 12 = y - 2x + 25
4x + 3y = 37
jika :
x = 1, y = 11
x = 4, y = 7
x = 7, y = 3
maka banyak nilai p = 3