Chapter 4.5, Problem 61E

To determine

To simplify the following expression $-5a^7·\left(-4a^2\right)$

Answer to Problem 61E

  $20a^9$

Explanation of Solution

Given information: Simplify $-5a^7·\left(-4a^2\right)$

This answer shall be derived using the product of powers rule, wherein the exponents of a common base can be added during multiplication and subtracted during division.

Calculation:

Given, $-5a^7·\left(-4a^2\right)$

  $=-5\times -4\times a^7\times a^2$ Here, the product on powers for ‘a’ is applicable

  $=20a^{7+2}$ ; multiplying a negative number with another negative number, would give a positive.

  $=20a^9$ This is the simplified expression