Solve x2-4x-7=0 by completing the square
2 answers:
HEY mate here is pratyush from India for your help...
the answer is with the attachment
hope it helps you..
the answer is with the attachment
hope it helps you..
Answer:
x = 2 ±
Step-by-step 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 = ± ( add 2 to both sides )
x = 2 ± ← exact solutions
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