Answer
$\approx 84.9$ feet
Work Step by Step
(a) See image below.
(b) To find the distance from home plate to second base, we divide the square in two pieces to form a right triangle.
We know that for a right triangle the Pythagorean Theorem states:
$leg_1^2+leg_2^2=hypotenuse^2$
$a^2+b^2=c^2$
Our legs are 60 ft long, so we have:
$60^2+60^2=c^2$
$3600+3600=c^2$
$7200=c^2$
$c=\sqrt{7200}$
$c\approx 84.9$ feet