Expanding (2x - 7)^2
The expression (2x - 7)^2 represents the square of a binomial. To expand this, we can apply the FOIL method or use the square of a difference pattern.
Using the FOIL method
FOIL stands for First, Outer, Inner, Last. This method helps us multiply two binomials by systematically considering all possible product combinations.
- First: Multiply the first terms of each binomial: (2x) * (2x) = 4x^2
- Outer: Multiply the outer terms of the binomials: (2x) * (-7) = -14x
- Inner: Multiply the inner terms of the binomials: (-7) * (2x) = -14x
- Last: Multiply the last terms of each binomial: (-7) * (-7) = 49
Now, we combine the terms: 4x^2 - 14x - 14x + 49
Finally, simplify by combining the like terms: 4x^2 - 28x + 49
Using the Square of a Difference Pattern
The square of a difference pattern states: (a - b)^2 = a^2 - 2ab + b^2
Applying this to our expression:
- a = 2x
- b = 7
Substituting these values into the pattern:
(2x)^2 - 2(2x)(7) + 7^2 = 4x^2 - 28x + 49
Therefore, both methods lead to the same expanded form: 4x^2 - 28x + 49
This expanded form represents a quadratic expression which can be further manipulated or used in different mathematical contexts.