Answer:
[tex]\boxed{\sf D)\:-24a^3b^7}[/tex]
Step-by-step explanation:
[tex]\sf (3a^2b^4)(-8ab^3)[/tex]
We'll use rule of exponents to simplify expression.
[tex]\sf 3^1a^2b^4(-8)^1a^1b^3[/tex]
Now, use the commutative property of multiplication.
[tex]\sf 3^1(-8)^1a^2a^2b^4b^4[/tex]
In order to multiply power of the same base, we add their exponents.
[tex]\sf 3^2(-8)^1a^{2+1}b^{4+3}[/tex]
→ Add exponents:
[tex]\sf 3^1(-8)^1a^3b^7[/tex]
→ Multiply 3* -8
[tex]\sf -24a^3b^7[/tex]
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