1.

Using suitable identity (7x-9y) (7x-9y)

Answer» (a - b)(a - b) = {a}^{2} + {b}^{2} - 2ab \\ \\ (7x - 9y)(7x - 9y) \\ = {(7x)}^{2} + {(2y)}^{2} - 2(7x)(9y) \\ = 49 {x}^{2} + 81 {y}^{2} - 126xy
HOPE helps

▪▪▪▪▪

☆☆☆☆☆
♡♡♡♡♡


Discussion

No Comment Found

Related InterviewSolutions