Step-by-step explanation:
[tex]third \: term = ( \frac{1}{2} \times coefficient\: of \:x)^{2} \\ \\ = ( \frac{1}{2} \times \frac{ - 2}{7} )^{2} \\ \\ = ( \frac{ - 1}{7} )^{2} \\ \\ = \frac{1}{49} [/tex]
So, you need to add [tex] \frac{1}{49}[/tex] on both sides of the quadratic equation.
