Step-by-step explanation:
Conversion of a quadratic equation from standard form to vertex form is done by completing the square method.
Assume the quadratic equation to be
where x is the variable.
Completing the square method is as follows:
- send the constant term to other side of equal
![\mathbf{ax^(2)+bx=-c}](https://img.qammunity.org/2020/formulas/mathematics/middle-school/jhce3soq02pm91nxbly0f83511fyyd7p0s.png)
- divide the whole equation be coefficient of
, this will give
![\mathbf{x^(2)+(b)/(a)x=- (c)/(a)}](https://img.qammunity.org/2020/formulas/mathematics/middle-school/eorzrjmin4su8kirjqt6tn8my96py5p5eb.png)
- add
to both side of equality
![\mathbf{x^(2)+2*(b)/(2a)x+(b)/(2a)^(2)=-(c)/(a)+(b)/(2a)^(2)}](https://img.qammunity.org/2020/formulas/mathematics/middle-school/y4243eh7wldh01qvnwy82ewtg4146ddelb.png)
- Make one fraction on the right side and compress the expression on the left side
![\mathbf{(x+(b)/(2a))^(2)=(b^(2)-4ac)/(4a^(2))}](https://img.qammunity.org/2020/formulas/mathematics/middle-school/bml1mbkxr66sl0br0jfdl3u7y0ysgb1jv8.png)
- rearrange the terms will give the vertex form of standard quadratic equation
![\mathbf{a(x+(b)/(2a))^(2)-(b^(2)-4ac)/(4a)=0}](https://img.qammunity.org/2020/formulas/mathematics/middle-school/xdyvzko4z1nijny8gdwh5kkzr79ertnxef.png)
Follow the above procedure will give the vertex form.
(NOTE : you must know that
. Use this equation in transforming the equation from step 3 to step 4)