Question

Solve the equation 2x(square)+ 4x- 16=0 by Completing square method.

Answer 1

2 x sq +4 x -16 = 0
4+(-64x)
60=x
x=60
mark as brilliant

Answer 2

x= -4,2

Given:

2x(square)+ 4x- 16=0

To find:

Solve the equation 2x(square)+ 4x- 16=0 by Completing square method.

Solution:

Quadratic Equation is ,

==> 2x² + 4x - 16 = 0

We have to factories by, Complete Square method

First we will take  constant part in R.H.S.

==> 2x² + 4x = 16

Now we will divide by " 2 " on both sides

==> 1/2 * ( 2x² + 4x ) = 16/2

==> 2x²/2 + 4x/2 = 8

==> x² + 2x = 8

Now, we will add 1 to both sides

==> x² + 2x + 1 = 8 + 1

==> x² + 2 * x * 1 + 1² = 9  [ 1 can be written as 1²]

We know

★ (a+b)² = a² + b² + 2ab

So,

a = x and b = 1

==> (x + 1)² = 9

==> (x + 1) = ± √9

==> x + 1 = ± 3

Take first (-)ve Sign

==> x + 1 = -3

==> x = -3 - 1

==> x = -4

Take Second (+) ve sign

==> x + 1 = 3

==> x = 3 - 1

==> x = 2

Hence value of x is -4 and 2.

#SPJ2