Question

simplify:
(3√5-5√2) (4√5+3√2)

Answer 1

Open the brackets

$(3 \sqrt{5} - 5 \sqrt{2} )(4 \sqrt{5} + 3 \sqrt{2} ) \\ \\ = > 3 \sqrt{5} (4 \sqrt{5} + 3 \sqrt{2} ) - 5 \sqrt{2} (4 \sqrt{5} + 3 \sqrt{2} ) \\ \\ = > 3 \sqrt{5} (4 \sqrt{5} ) + 3 \sqrt{5} (3 \sqrt{2} ) - 5 \sqrt{2} (4 \sqrt{5} ) - 5 \sqrt{2} (3 \sqrt{2} ) \\ \\ = > 12 \times 5 + 9 \sqrt{10} - 20 \sqrt{10} - 15 \times 2 \\ \\ = > 60 - 11 \sqrt{10} - 30 \\ \\ = > 30 - 11 \sqrt{10}$

Answer 2

Please see the attachment