(i) (5-2x)(3+2)=5x(3+x)-2x(3+x)= 5×3+5xX-2xX3-2xx3-2xXx
= 15+5x-6x-2x²=15-x-2x²

(ii) (x+7y)(7x-y)= x(7x-y)+7yx(7x-y)
= xx7x-Xxy+7yx7x-7yxy
= 7x²-xy+49xy-7y²
= 7x²+48xy-7y²

Class 8 Maths Chapter 9 Exercise 9.4 Solution in Video

for more answers vist to:
https://www.tiwariacademy.com/ncert-solutions/class-8/maths/chapter-9/