90=(x+3)+(x-1)+(x+1)

Solution for 90=(x+3)+(x-1)+(x+1) equation:

90=(x+3)+(x-1)+(x+1)

We move all terms to the left:

90-((x+3)+(x-1)+(x+1))=0


We calculate terms in parentheses: -((x+3)+(x-1)+(x+1)), so:

(x+3)+(x-1)+(x+1)

We get rid of parentheses

x+x+x+3-1+1

We add all the numbers together, and all the variables

3x+3

Back to the equation:

-(3x+3)


We get rid of parentheses

-3x-3+90=0

We add all the numbers together, and all the variables

-3x+87=0

We move all terms containing x to the left, all other terms to the right

-3x=-87

x=-87/-3

x=+29