Question

factorise 7x²y-21xy²​

Answer 1

⇒ p(x)=7x²y-21xy²
Putting p(x)=0
⇒ 7xy.(x-3y)=0
⇒ 7xy=0 and x-3y=0
⇒ 21y²=0 x=3y
⇒ y=0 and x=0

Ans:-y=0 and x=0