Answer:
Enter the equations.
Multiply each equation by a number to get the lowest common multiple for one of the variables.
Add or subtract the two equations to eliminate that variable .
Substitute that variable into one of the equations and solve for the other variable.
Given:

To find:
The missing value.
Solution:
Let x be the missing value.
We have,


Subtract
from both sides.




Multiplying both sides by 5, we get

So, the missing value is 3.
Therefore, the correct option is C.
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