1)
4x + 5y = 40
4x + 5y - 40 = 40 -40
4x + 5y - 40 = 0
2)
4x + 5y = 40 y = 0
4x +5×0 = 40
4x = 0 = 40
4x = 40
x = 10
1)
4x + 5y = 40
4x + 5y - 40 = 40 -40
4x + 5y - 40 = 0
2)
4x + 5y = 40 y = 0
4x +5×0 = 40
4x = 0 = 40
4x = 40
x = 10