Quadratic equation

  I have choose a quadratic equation as a common question . This is for both GCSE & A-level student. (2x)^2-x-1=0
To solve this equation we have four methods:- Factoring Completing square Quadratic formulae By graph
I will demonstrate the 3rd method which is quadratic formulae.
Each quadratic equation has two possible answers called roots.By using 3rd method we can find out the roots of the equation and check the behaviour of equation .
X=(-b±√(b^2-4ac) )/2a
Step1:-
     Compare quadratic equation to the standard form of quadratic    equation to get the coefficient of quadratic equation, which is :-     ax^2+bx+c=0By comparing we get a= 2, b=-1,c=-1
Step2:-
   Now put values of a, b, c in quadratic formulaX=(-(-1)±√((-1)^2-4(2)(-1) ) )/2(2)
Now solve the above equation
X=(1±√(1+8) )/4
X=(1±√9 )/4                                     ∴ √9=3
X=(1±3)/4
   It include two answer due to the sign of ‘±^' in above equation

Step3:-
To get answer split the above equation x=(1±3)/4 in two part,
part 1:-     x=(1+3)/4
part 2:-
x=(1-3)/4
Step4:-
Solving of part 1 and part 2 we get:-
X=4/4=1
X=-2/4=-1/2Answer
X=(1,-1/2 )