Simplifying the Expression (-x-9)(x-9)+x(x+18)
This article will guide you through the steps of simplifying the expression (-x-9)(x-9)+x(x+18). We will use the distributive property and combining like terms to reach a simplified form.
Step 1: Expanding the Products
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First, we expand the first product: (-x-9)(x-9)
- Using the FOIL method (First, Outer, Inner, Last):
- First: -x * x = -x²
- Outer: -x * -9 = 9x
- Inner: -9 * x = -9x
- Last: -9 * -9 = 81
- Combining the terms: -x² + 9x - 9x + 81 = -x² + 81
- Using the FOIL method (First, Outer, Inner, Last):
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Next, we expand the second product: x(x+18)
- Using the distributive property:
- x * x = x²
- x * 18 = 18x
- Combining the terms: x² + 18x
- Using the distributive property:
Step 2: Combining Like Terms
Now we have the expression: -x² + 81 + x² + 18x
- Notice that the -x² and x² terms cancel each other out.
- This leaves us with 81 + 18x
Step 3: Final Simplified Form
The simplified form of the expression (-x-9)(x-9)+x(x+18) is 81 + 18x.