The problem in the image asks to evaluate the expression $6c - b$ given that $a = 2$, $b = 7$, and $c = 6$.

To solve:

1. Substitute $c = 6$ and $b = 7$ into the expression $6c - b$: $6(6) - 7 = 36 - 7 = 29$

The result is 29.

Would you like more details or explanations?

Here are some related questions to deepen understanding:

1. How would the result change if $b = 9$?
2. What would the expression look like if it included all three variables $a$, $b$, and $c$?
3. How can you express $6c - b$ graphically for different values of $c$?
4. How would the evaluation change if the expression was $6b - c$?
5. How can this concept be applied to solving systems of equations?

Tip: When substituting values into an expression, be sure to follow the correct order of operations (PEMDAS).