Answer:
c, d, a, b.
Step-by-step explanation:
I'm presuming that the original equation is
.
First, isolate c. You can do this by subtracting
from both sides:
Next, simplify to
.
Then, divide both sides by 7: 
Finally, simplify to
.
The result of division is 21.392
Rounded to the nearest tenth its 21.4 answer
(because the hundredth digit is 9 so you add 1 to the tenth digit.)
In the attached diagram you can see Place Value Chart that is used to help understand the value of each digit based on the place or position.
For the number 756:
- 7 has a value of 7 hundreds, or 700;
- 5 has a value of 5 tens, or 50;
- 6 has a value of 6 ones, or 6.
Answer: 5 has a value of 5 tens, or 50