Respuesta :

[tex]D:x > 0\ and\ x\neq1\\\\log_x8=0.5\iff x^{0.5}=8\ \ \ \ |square\ of\ both\ sides\\\\\left(x^{0.5}\right)^2=8^2\\\\x=64\\\\check:\\log_{64}8=0.5\iff64^{0.5}=8\to 64^\frac{1}{2}=\sqrt{64}=8[/tex]