Answer: B
Step-by-step explanation:
In this equation, you must find the common denominator of each fraction, and subtract them.
Given:
3/8b - 3/4b
Step 1: Find the common denominator
As 4 is a factor of 8, multiply the entire fraction by 2 to get the common denominator.
3/8b - 2(3/4b)
3/8b - 6/8b
This is the proper equation
Step 2: Solve
Subtract 6/8b from 3/8b to get the solution
3/8b - 6/8b = -3/8b
The answer is B