Question

Multiply.................

Answer 1

It’s B.
Distribute the 7a and multiply it with the 3a and -4 a. With the exponents you add them.

Answer 2

For this case we must solve the following product:

`-7a ^ 2 (3a ^ 3-4a ^ 5)`

We know that, by definition, the distributive property states that:

`a (b + c) = ab + ac`

Also, by definition, we know that:

`x ^ n * x ^ m = x ^ {m + n}`

On the other hand, we have to:

`+ * - = -\\- * - = +`

So:

Resolving, multiplying term by term, taking into account the previous definitions, we have:

`-7a ^ 2 (3a ^ 3-4a ^ 5) = - 21a ^ 5 + 28a ^ 7`

Answer:

option b