Expanding the Expression (x+5)(x^2+4x-8)
This article will guide you through the process of expanding the given expression: (x+5)(x^2+4x-8).
Understanding the Problem
We have two expressions:
- (x+5): This is a binomial (an expression with two terms).
- (x^2+4x-8): This is a trinomial (an expression with three terms).
Our goal is to multiply these two expressions together to obtain a simplified expression.
Using the Distributive Property
The distributive property is the key to expanding the expression. It states that multiplying a sum by a number is the same as multiplying each term of the sum by that number.
Here's how we apply it:
-
Distribute (x+5) over each term of (x^2+4x-8):
- x(x^2+4x-8): This represents multiplying the first term of (x+5) with each term of (x^2+4x-8).
- 5(x^2+4x-8): This represents multiplying the second term of (x+5) with each term of (x^2+4x-8).
-
Simplify each individual multiplication:
- x(x^2+4x-8) = x^3 + 4x^2 - 8x
- 5(x^2+4x-8) = 5x^2 + 20x - 40
-
Combine the results:
- (x^3 + 4x^2 - 8x) + (5x^2 + 20x - 40)
-
Combine like terms:
- x^3 + (4x^2 + 5x^2) + (-8x + 20x) - 40
-
Final simplified expression:
- x^3 + 9x^2 + 12x - 40
Conclusion
By applying the distributive property, we successfully expanded the expression (x+5)(x^2+4x-8) to obtain the simplified form x^3 + 9x^2 + 12x - 40. This process demonstrates the importance of understanding the distributive property in algebra.