Question

If x/y + y/x =2, Then 4x-4y-4 = ? ( Please show with full process and don't spam )​

Answer 1

`\\ \sf\longmapsto (x)/(y)+(y)/(x)=2`

`\\ \sf\longmapsto (x^2+y^2)/(xy)=2`

`\\ \sf\longmapsto x^2+y^2=2xy`

`\\ \sf\longmapsto x^2+y^2-2xy=0`

`\boxed{\sf (a-b)^2=a^2-2ab+b^2}`

`\\ \sf\longmapsto (x-y)^2=0`

`\\ \sf\longmapsto x-y=√(0)`

`\\ \sf\longmapsto x-y=0`

Now

`\\ \sf\longmapsto 4x-4y-4`

• take 4common

`\\ \sf\longmapsto 4(x-y-4)`

• Put the value

`\\ \sf\longmapsto 4(0-4)`

`\\ \sf\longmapsto 4(-4)`

`\\ \sf\longmapsto -16`