Question

Find the square: (5x - 4y)2

(and please put the process of solving the equation)

Answer 1

`(5x-4y)^2`

`(5x-4y)(5x-4y)`

Multiply each term in one bracket in turn by the terms in the other bracket


`(5x)(5x) = 25x^2`

`(5x)(-4y)=-20xy`

`(-4y)(5x)=-20xy`

`(-4y)(-4y)=16y^2`

Put them together we have

`25x^2-20xy-20xy-16y^2`

`25x^2-40xy-16y^2`