Question

ABCD is a rectangle whose three vertices are B(4, 0), C(4, 3) and D(0, 3). The length of one of its diagonals is [CBSE 2014]
(a) 5 (b) 4 (c) 3 (d) 25

Answer 1

Here, AC and BD are two diagonals of the rectangle ABCD. So
$$\begin{gathered} BD=\sqrt{{\left(4-0\right)}^2+{\left(0-3\right)}^2} \\ =\sqrt{{\left(4\right)}^2+{\left(-3\right)}^2} \\ =\sqrt{16+9} \\ =\sqrt{25} \\ =5\mathrm{units} \end{gathered}$$
Hence, the correct answer is option (a).