guys here i dont understand how she did the highlighted part i dont understand how she went from X^2… TO X^2 +2(5/4)x…)

and if you have another way for solving this, pls mention it.

thanks

guys here i dont understand how she did the highlighted part i dont understand how she went from X^2… TO X^2 +2(5/4)x…)

and if you have another way for solving this, pls mention it.

thanks