Resposta:
Explicação passo-a-passo:
[tex]x^2-mx+\frac{m^2}{4}=0\\\\x^2\cdot \:4-mx\cdot \:4+\frac{m^2}{4}\cdot \:4=0\cdot \:4\\\\4x^2-4mx+m^2=0\\\\x_{1,\:2}=\frac{-\left(-4m\right)\pm \sqrt{\left(-4m\right)^2-4\cdot \:4m^2}}{2\cdot \:4}\\\\x_{1,\:2}=\frac{-\left(-4m\right)\pm \sqrt{0}}{2\cdot \:4}\\\\x=\frac{-\left(-4m\right)}{2\cdot \:4}\\\\x=\frac{m}{2}\\[/tex]
