Which expressions are equivalent to 4b? options: b+2(b+2b) 3b+b none of the above

3b+b because 3+1=4 just add b and replace 1 with b
b is the same as 1
3b is the same as 3

4b :     b + 2(b + 2b)     OR     3b + b

First option : 

b + 2(b + 2b)

Simplify.

b + 2b + 4b

Simplify.

3b + 4b

Simplify.

7b

So, the first option is INCORRECT.

Second option :

3b + b

Simplify.

4b

So, our second option is CORRECT.

3b + b

~Hope I helped!~