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Solve x2-4x-7=0 by completing the square ​

2 Answers

4 votes

Answer:

x = 2 ±
\sqrt11}

Explanation:

Given

x² - 4x - 7 = 0 ( add 7 to both sides )

x² - 4x = 7

To complete the square

add (half the coefficient of the x- term)² to both sides

x² + 2(- 2)x + (- 2)² = 7 + (- 2)²

(x - 2)² = 7 + 4 = 11 ( take the square root of both sides )

x - 2 = ±
√(11) ( add 2 to both sides )

x = 2 ±
√(11) ← exact solutions

User Hor Chanpheng
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5.4k points
5 votes
HEY mate here is pratyush from India for your help...

the answer is with the attachment

hope it helps you..
Solve x2-4x-7=0 by completing the square ​-example-1
User Michal Klouda
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5.3k points