Precalculus: Concepts Through Functions, A Unit Circle Approach to Trigonometry (3rd Edition)

$\sqrt{3.69}\approx1.92$
The distance between the points $P_1=(x_1, y_1)$ and $P_2=(x_2, y_2)$, is given by the formula: $d(P_1, P_2)=\sqrt{(x_2-x_1)^2+(y_2-y_1)^2}$ If we plug in the coordinates of the two given points given into the formula above, we'd have: $d(P_1, P_2)=\sqrt{(-0.3-1.2)^2+(1.1-2.3)^2}=\sqrt{2.25+1.44}=\sqrt{3.69}\approx1.92$