Answer:
A.
Step-by-step explanation:
All of them are wrong except for the third one
The first one is 10ab + 20
Answer:
The answer is C
Step-by-step explanation:
You need to find a common denominator and in this case its 20. SO you change 3/4ths to 15/20 and 4/5ths to 16/20ths and 19/20 stays the same. Then you cancel out the 20 because its all the same number (I think) and you have your answer.