please jawab dong? saya ga tahu caranya

(2√5 + 2)(3√5 - 1) = 2√5(3√5) - 2√5 + 2(3√5) - 2
                             = 6 (5) - 2√5 +6√5 - 2
                             = 30 + 4√5 - 2
                             = 28 + 4√5