Answer
$\approx 8.54$ units
Work Step by Step
Use the distance formula $d=\sqrt{(x_1-x_2)^2+(y_1-y_2)^2}$ to obtain:
$d=\sqrt{(2-(-1))^2+(-3-5)^2}
\\d=\sqrt{(2+1)^2+(-8)^2}
\\d=\sqrt{3^2+64}
\\d=\sqrt{9+64}
\\d=\sqrt{73}
\\d \approx 8.54$