Question

(7x + 8y)² = .....
(2a - 3b)² = .....

Answer 1

(7x + 8y)^2 = (7x + 8y) (7x + 8y)
                 = 7x^2 + 54xy + 54xy + 8y^2
                 = 7x^2 + 108xy +8y^2

(2a - 3b)^2 = (2a - 3b) (2a - 3b)
                = 2a^2 - 6ab - 6ab + 9b^2
                = 2a^2 -12ab + 9b^2

KET : ^2 = pangkat dua (2)