Question

(2x9y^n)(4x2y10)=8x11y20

Answer 1

`(2x^9y^n)(4x^2y^(10))=8x^(11)y^(20)\\\\(2\cdot4)(x^9\cdot x^2)(y^n\cdot y^(10))=8x^(11)y^(20)\\\\8x^(9+2)y^(n+10)=8x^(11)y^(20)\\\\8x^(11)y^(n+10)=8x^(11)y^(20)\Rightarrow n+10=20\ \ \ |-10\\\\\boxed{n=10}`


`\text{Used:}\\a^n\cdot a^m=a^(n+m)`