You have provided the equation $ab + d = c$. Here are a few ways we can approach this equation:

1. Isolate $d$: To solve for $d$, we can rearrange the equation as: $d = c - ab$

2. Solve for $b$: If you want to solve for $b$, the equation becomes: $ab = c - d \quad \Rightarrow \quad b = \frac{c - d}{a}, \quad \text{assuming} \ a \neq 0.$

3. Solve for $a$: Similarly, if solving for $a$, we get: $ab = c - d \quad \Rightarrow \quad a = \frac{c - d}{b}, \quad \text{assuming} \ b \neq 0.$

4. If you're given specific values for $a$, $b$, $c$, or $d$: We could substitute those values into the equation to find the unknowns.

Do you have specific values or variables you're trying to solve for? Would you like me to expand on one of the solutions?

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Here are some related questions:

1. How would you approach solving for $d$ when given specific values for $a$, $b$, and $c$?
2. What happens when either $a$ or $b$ equals zero in the equation $ab + d = c$?
3. How can this equation be used in real-world applications (e.g., physics or economics)?
4. How would the equation change if it was part of a system of equations?
5. What if the equation had more terms, like $ab + d + e = c$?

Tip: Always check for any restrictions on variables (like dividing by zero) when solving equations.