X square + 2 x minus 5 equal to zero solve by completing square method
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x² + 2x - 5 = 0
add 5 to both side
x² + 2x = 5
divide the coefficient of x by 2 , then square the resultant.
2/2 = 1 ; 1² = 1
add the resultant i.e., 1 to both side
x² + 2x + 1 = 5 + 1
x² +2x + 1 = 6
x² + 2x + 1 can be written as (x + 1)²
(x + 1)² = 6
taking square root of both side
x + 1 = √6 OR x +1 = -√6
x = √6 - 1 OR x = -√6 - 1
So the two zeroes are
√6 - 1 & -√6 - 1
add 5 to both side
x² + 2x = 5
divide the coefficient of x by 2 , then square the resultant.
2/2 = 1 ; 1² = 1
add the resultant i.e., 1 to both side
x² + 2x + 1 = 5 + 1
x² +2x + 1 = 6
x² + 2x + 1 can be written as (x + 1)²
(x + 1)² = 6
taking square root of both side
x + 1 = √6 OR x +1 = -√6
x = √6 - 1 OR x = -√6 - 1
So the two zeroes are
√6 - 1 & -√6 - 1
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