Question 10Point $P$ is taken interior to a square with side-length $a$ and such that it is equally distant from two consecutive vertices and from the side opposite these vertices. If $d$ represents the common distance, then $d$ equals:$\dfrac{3a}{5}$$\dfrac{5a}{8}$$\dfrac{3a}{8}$$\dfrac{a\sqrt2}{2}$$\dfrac a2$