bantu ya kak, matematika, pointnya banyak tuh :)

cara cepat : EP = a/2√6 = 20/2 √6 = 10√6

cara biasa :
AP = 1/2 AC

AC= √(20²+20²) = √800 = 20√2
AP = 1/2 x 20√2 = 10√2

EP = √(EA²+AP²)
= √[20²+(10√2)²]
= √400 + 200
= √600
= 10√6

jawaban : B