Answer: 28 red marbles
Step-by-step explanation:
Since there are in total 140 marbles and there are 5 red marbles, just simply divide 140 by 5 and you get your answer. 28 red marbles.
1. 12a+6=12a+6
2. 12a+6=12a+2
3. 12a+6=4a+6
4. 12a+6=7a+5
YES IT IS RIGHT.YOU ARE RIGHT