Question

How do you solve `4(u+1)+5=6(u-1)+u`?

Answer 1

`u=5`

Explanation:

Distribute brackets on both sides of the equation.

`4u+4+5=6u-6+u`

`"simplify both sides"`

`4u+9=7u-6`

`"subtract 7u from both sides"`

`4u-7u+9=cancel(7u)cancel(-7u)-6`

`rArr-3u+9=-6`

`"subtract 9 from both sides"`

`-3ucancel(+9)cancel(-9)=-6-9`

`rArr-3u=-15`

`"divide both sides by - 3"`

`(cancel(-9) u)/cancel(-9)=(-15)/(-3)`

`rArru=5`

`color(blue)"As a check"`

Substitute this value into the equation and if both sides are equal then it is the solution.

`"left side "=4(5+1)+5=(4xx6)+5=24+5=29`

`"right side "=6(5-1)+5=(6xx4)+5=29`

`rArru=5" is the solution"`