(1) x + 5 = 3x
⟹ 3x - x = 5⇒ 5 = 2x∴ x = 52(2) 7x = 20 − x⇒ 8x = 20⇒ x = 208∴ x = 52(3) 6(x − 1) = 5(x + 1)⇒ 6x − 6 = 5x + 5⇒ − 6 = − x + 5⇒ − 11 = − x∴ x = 11(4) 2x + 3 = 3(x − 1)⇒ 2x + 3 = 3x − 3⇒ 3 = x − 3∴ x = 6