The expression provided is:

$-b^2 + 1 - 7d^2$

To determine the coefficient of the first term, $-b^2$, we need to identify the constant that multiplies $b^2$.

In this case, the first term is $-b^2$, where the coefficient is $-1$.

Answer: The coefficient of the first term is $-1$.

Would you like further details or have any questions?

Here are some additional questions for practice:

1. What is the coefficient of $d^2$ in the expression $-b^2 + 1 - 7d^2$?
2. What is the constant term in the expression $-b^2 + 1 - 7d^2$?
3. If we added a term $3c$ to the expression, what would be the coefficient of $c$?
4. How would the expression change if the coefficient of $b^2$ was changed to $2$?
5. What would the expression look like if we combined like terms (if there were any)?

Tip: Remember, coefficients are the numbers directly in front of variables in terms.