Understanding (x - 10)(x - 10)
The expression (x - 10)(x - 10) is a product of two binomials, both of which are identical. This means it represents a special case of multiplication that has a specific pattern and can be simplified.
Expanding the Expression
To understand what (x - 10)(x - 10) represents, we need to expand it. This involves using the distributive property of multiplication.
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Distribute the first term (x) of the first binomial:
- x * (x - 10) = x² - 10x
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Distribute the second term (-10) of the first binomial:
- -10 * (x - 10) = -10x + 100
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Combine the results from steps 1 and 2:
- x² - 10x - 10x + 100
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Simplify by combining like terms:
- x² - 20x + 100
Recognizing the Pattern: Perfect Square Trinomial
The expanded form, x² - 20x + 100, is a perfect square trinomial. This means it follows a specific pattern:
- The first term (x²) is the square of the first term of the binomial (x).
- The last term (100) is the square of the second term of the binomial (10).
- The middle term (-20x) is twice the product of the first and second terms of the binomial (2 * x * -10 = -20x).
Using the Pattern for Simplification
Knowing this pattern allows us to directly simplify expressions like (x - 10)(x - 10) without going through the full expansion process:
- Square the first term: x²
- Multiply the two terms and double the result: 2 * x * -10 = -20x
- Square the second term: (-10)² = 100
- Combine the terms: x² - 20x + 100
This pattern helps us quickly and efficiently simplify expressions involving identical binomials.