Answer:
The answer is
→ 1.5 or 10x = 15
Step-by-step explanation:
Since 10x + 6 = 21 and we supposed to find what 15 is, we would have to use these steps;
First subtract 6 on both sides
10x + 6 - 6 = 21 - 6
= 10x = 15
Another way I know the other answer is by multiplying 10 by 1.5 which equals 15.
