Math Help - Completing the square

1. Completing the square

2x2 + 8x - 3 = 0

My method:
$2((x^2+8x+16)-16)-3\longrightarrow 2((x+4)^2-16)-3 \longrightarrow 2(x+4)^2=35$

2. Originally Posted by Mukilab
2x2 + 8x - 3 = 0

My method:
$2((x^2+8x+16)-16)-3\longrightarrow 2((x+4)^2-16)-3 \longrightarrow 2(x+4)^2=35$
$2(x+4)(x+4)=35\ is\ 2x^2+16x+32=35$

which is $2x^2+16x-3=0$

Instead $2x^2+8x=3$

$x^2+4x=\frac{3}{2}$

$x^2+2(2x)+2^2-2^2=\frac{3}{2}$

$(x+2)^2-4=\frac{3}{2}$

$(x+2)^2-\frac{11}{2}=0$

$2(x+2)^2-11=0$