Answer is -3
Step-by-step explanation:
The leading term of a polynomial is the term with the largest exponent, which in this case that exponent is 4. So the leading term is -3x^4.
The leading coefficient is the coefficient of the leading term. The coefficient of the term -3x^4 is -3.
If the polynomial is written in standard form, then the process is as simple as reading the first coefficient. Otherwise, you may have to sort the terms out first.