Question

solve be completing the square:
x^2+7x-4=0

Answer 1

Add and substract LHS by 49/4
\[x^{2}-7x+\frac{ 49 }{ 4 }-\frac{ 49 }{ 4 }-4=0\]
\[[x-\frac{ 7 }{ 2 }]^{2}-\frac{ 65 }{ 4 }=0\]
\[[x-\frac{ 7 }{ 4 }]^2=\frac{ 65 }{ 4 }\]
further take square root and solve further....