Question 250306
2b+4(b-1)=5(b-1)
there are at least two ways to do this. one easy and one easier
we can subtract 4(b-1) from both sides
2b=1(b-1)
2b=b-1
subtract b from both sides
b=-1

another way 
2b+4(b-1)=5(b-1)
expand 
2b+4b-4=5b-5
combine like terms
6b-4=5b-5
subtract 5b from both sides
b-4=-5
add 4 to both sides
b=-1