so you want to add lik terms first
group them together
I have gropued the like terms using brackets
[-2x+(x/4)]+[-6-3+90]=180
add lik terms
add the number terms
-6-3+90=81
[-2x+(x/4)]+[81]=180
subtract 81 from both sides
-2x+(x/4)=99
add 2x to both sides
x/4=99+2x
multipliy both sides by 4 to clear fraction
x=396+8x
subtract 8x from both sides
-7x=396
mulitply both sides by -1
7x=-396
divide both sides by 7
x=-396/7=-56 and 4/7