Question

how to find roots with the method of complete the square

Answer 1

let any quadratic equation ,
ax^2+bx+c=0
first divide a both side
x^2+(b/a)x +c/a=0
x^2+(b/a) x=-c/a
now add (b/2a)^2 both side
x^2+(b/a) x +(b/2a)^2=-c/a +(b/2a)^2
x^2+2. (b/2a).x+(b/2a)^2=(b^2-4ac)/4a^2
(x+b/2a)^2=(b^2-4ac)/4a^2
take square root both side
x+b/2a= +_root (b^2-4ac)/2a
x={-b+_root(b^2-4ac)}/2a

I hope this process helpful to you