Simplifying the Expression (5c - 3d)² - 9d²
This article will guide you through simplifying the algebraic expression (5c - 3d)² - 9d². We'll use the properties of exponents and the distributive property to arrive at a simplified form.
Understanding the Components
- (5c - 3d)²: This represents the square of the binomial (5c - 3d).
- - 9d²: This is a simple monomial term.
Simplifying the Expression
-
Expand the square:
- Recall that squaring a binomial means multiplying it by itself: (5c - 3d)² = (5c - 3d)(5c - 3d)
- Use the FOIL (First, Outer, Inner, Last) method to expand the product:
- First: 5c * 5c = 25c²
- Outer: 5c * -3d = -15cd
- Inner: -3d * 5c = -15cd
- Last: -3d * -3d = 9d²
- Combine the like terms: 25c² - 15cd - 15cd + 9d² = 25c² - 30cd + 9d²
-
Combine terms with the monomial:
- Now our expression is: 25c² - 30cd + 9d² - 9d²
- The 9d² and -9d² terms cancel each other out.
-
Final simplified expression:
- The simplified expression is 25c² - 30cd.
Conclusion
By applying the distributive property and combining like terms, we successfully simplified the expression (5c - 3d)² - 9d² to 25c² - 30cd. This process demonstrates how algebraic manipulations can lead to a more concise and manageable form of an expression.