Question

1. $-5x^{3} cdot (-3x^{4})$

Explanation:

Step1: Multiply the coefficients

$(-5) \times (-3) = 15$

Step2: Multiply the variable terms

$x^3 \times x^4 = x^{3+4} = x^7$

Step3: Combine the results

$15 \times x^7$

Answer:

$15x^7$