Question

Factorisation - 15m+9-35mn-21n

Answer 1

Thts easy!

15m+9-35mn-21n

=3(5m+3)-7n(5m+3)

=(3-7n)(5m+3)

Answer 2

15m+9-35mn-21n

3(5m+3) -7n(5m+3)

(3-7n) (5m+3)

(-7n+3) (5m+3)

I hope it's helpful for you...