Mathematics for IGCSE & O level - Equations (Section 5 - No. 49)
If you have (x + 4)(x - 1) = 0, what are the solutions for x?
x = 4, x = 1
x = -4, x = -1
x = -4, x = 1
x = 4, x = -1
คำอธิบาย
Set each factor to zero: x + 4 = 0 => x = -4; x - 1 = 0 => x = 1.