6x+2(3-x)-26=100

Wow, thanks!

Answer x=30

But how do i solve it?

6x+2(3-x)-26=100

6x+6-2x-26=100

6x-2x+6-26=100

4x-20=100

add 20 to both sides

4x-20+20=100+20

4x=120

divide both sides by 4

x=30

check

$${\mathtt{6}}{\mathtt{\,\times\,}}{\mathtt{30}}{\mathtt{\,\small\textbf+\,}}{\mathtt{2}}{\mathtt{\,\times\,}}\left({\mathtt{3}}{\mathtt{\,-\,}}{\mathtt{30}}\right){\mathtt{\,-\,}}{\mathtt{26}} = {\mathtt{100}}$$      GOOD