57=3+r+r+2(3+r)

Solution for 57=3+r+r+2(3+r) equation:

57=3+r+r+2(3+r)

We move all terms to the left:

57-(3+r+r+2(3+r))=0

We add all the numbers together, and all the variables

-(3+r+r+2(r+3))+57=0


We calculate terms in parentheses: -(3+r+r+2(r+3)), so:

3+r+r+2(r+3)

determiningTheFunctionDomain
r+r+2(r+3)+3

We add all the numbers together, and all the variables

2r+2(r+3)+3

We multiply parentheses

2r+2r+6+3

We add all the numbers together, and all the variables

4r+9

Back to the equation:

-(4r+9)


We get rid of parentheses

-4r-9+57=0

We add all the numbers together, and all the variables

-4r+48=0

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

-4r=-48

r=-48/-4

r=+12