Question

x²+2x-5=0 Solve this quadratic equation by completing the square method.

Answer 1

$\sf{GIVEN:-}$

x² + 2x - 5 = 0

So, we have to find to it's zeroes by using completing Square method.


x² + 2x - 5 = 0

we can write 2x = 2(x)(1)

x² + (2)(x)(1) + [ 1² - 1²] - 5 = 0

(x + 1)² - 1 - 5 = 0

[(x² + 2x + 1) = (x + 1)² , where, (a² + b² + 2ac = (a + b)²]

so,

(x + 1)² = 6

[taking Square Root both side]

(x + 1) = ±√6

now there is two situation

( 1 ) we have to take (+ve) sign.
So, answeer will be.

(x + 1) = √6

x = (√6 - 1)

( 2 ) we have to take (+ve) sign.
So, answeer will be.

(x + 1) = -√6

x = -(√6 + 1)

Answer 2

Hi ,

It is given that x²+ 2x - 5 = 0

x² + 2x = 5

x² + 2 × x × 1 + 1² = 5 + 1²

( x + 1 )² = 6

( x + 1 ) = ± √6

x = ±√6 - 1

x = √6 - 1 or x = -√6 - 1

I hope this helps you.

: )