By using the root formula i got $(2\pm \sqrt{8a})$ expression.
So, $ a $ cannot be negative and if $a$ is positive we get two solutions.
Therefore, $a=0$ is the answer??
Is my approach correct and is there a better way to solve this problem?
By using the root formula i got $(2\pm \sqrt{8a})$ expression.
So, $ a $ cannot be negative and if $a$ is positive we get two solutions.
Therefore, $a=0$ is the answer??
Is my approach correct and is there a better way to solve this problem?
Yes ,your approach is correct but is seems you incorrectly calculated the roots. It is enough to note that we seek a unique solution to
$$(x-2)^2=2a$$
This is only possible if $a=0$.
And the corresponding solutions are $2\pm \sqrt{2a}$.