Expanding the Expression (3x - 1)(4x + 5)
This article explores the process of expanding the algebraic expression (3x - 1)(4x + 5). We will utilize the FOIL method, a mnemonic for multiplying binomials, to achieve this.
FOIL Method Explained
FOIL stands for:
- First: Multiply the first terms of each binomial.
- Outer: Multiply the outer terms of the binomials.
- Inner: Multiply the inner terms of the binomials.
- Last: Multiply the last terms of each binomial.
Applying FOIL to (3x - 1)(4x + 5)
Let's apply the FOIL method to our expression:
- First: (3x)(4x) = 12x²
- Outer: (3x)(5) = 15x
- Inner: (-1)(4x) = -4x
- Last: (-1)(5) = -5
Now, combine the results:
12x² + 15x - 4x - 5
Finally, simplify by combining like terms:
12x² + 11x - 5
Conclusion
By applying the FOIL method, we successfully expanded the expression (3x - 1)(4x + 5) to obtain the simplified form 12x² + 11x - 5. This process is a fundamental skill in algebra, allowing you to manipulate and solve various equations and expressions.