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Use completing the square to solve for X in the equation (c+7)(x-9)=25

User Verbedr
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1 Answer

1 vote

Answer:

x = 1 ± √89

Explanation:

Step 1: Expand

x² - 2x - 63 = 25

Step 2: Isolate xs

x² - 2x = 88

Step 3: Complete the square

x² - 2x + 1 = 88 + 1

(x - 1)² = 89

Step 3: Square root both sides

√(x - 1)² = ±√89

x - 1 = ±√89

Step 4: Isolate x

x = 1 ± √89

User Brian Gottier
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