Multiplying Trinomials

The video tutorial explains how to simplify an algebraic expression by correctly distributing a negative sign across terms within parentheses. It highlights common mistakes, such as dropping parentheses without proper distribution, and provides a step-by-step guide to correctly simplify the expression by combining like terms.

What is the first step in simplifying the expression A + 2B + 3C - a(4A + 6B - 5C)?

Explain why dropping all parentheses in the expression is incorrect.

How do you distribute a negative sign in the expression?

What is the result of combining like terms in the expression after distribution?

Describe the process of simplifying the expression step by step.