Answer: c = 10, d = 7
Explanation:
To solve this system using the linear combination method, we want to eliminate one of the variables, either c or d, by adding or subtracting the two equations. One way to do this is to add the two equations together, which will cancel out the d terms:
(c + d) + (c - d) = 17 + 3
2c = 20
c = 10
Now we can substitute this value of c into either equation to solve for d:
c - d = 3
10 - d = 3
d = 7
Therefore, the solution to the system is:
c = 10, d = 7.