Question

Expand
$(5a - 3b) square$
​

Answer 1

$(5a - 3b) ^{2} \\ = (5a)^{2} + (3b) ^{2} - (2 \times 5a \times 3b) \\ = 25a^{2} + 9 {b}^{2} - (2 \times 15ab) \\ = 25 {a}^{2} + 9 {b}^{2} - 30ab$

Hope this helps you.