ОДЗ : x > 0
0\\\\m^{2} -4m-5=0\\\\D=4^{2} -4*(-5)=16+20=36=6^{2}\\\\m_{1}=\frac{4+6}{2}=5\\\\m_{2}=\frac{4-6}{2}=-1" alt="25^{lgx}=5+4x^{lg5}\\\\(5^{lgx})^{2}-4*5^{lgx}-5=0\\\\5^{lgx}=m,m>0\\\\m^{2} -4m-5=0\\\\D=4^{2} -4*(-5)=16+20=36=6^{2}\\\\m_{1}=\frac{4+6}{2}=5\\\\m_{2}=\frac{4-6}{2}=-1" align="absmiddle" class="latex-formula">
m₂ - не подходит, так как < 0
