5. Can someone explain how to solve this?
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Answer:
AC = 5 cm
BD = 12.5 cm (3 sf) [or 2 × root 39]
BE = 6.93 cm (3 sf) [or 4 × root 3]
Step-by-step explanation:
CE = 8cm [CE is radius of circle]
AC + 3 = 8
AC = 5 cm
BC = 8cm [BC is a radius of circle]
(AC)^2 + (AB)^2 = (BC)^2 [Pythagoras theorem]
25 + (AB)^2 = 64
AB = 6.2450 cm (5 sf) [or root 39]
BD = 2(BA)
= 2(6.2450)
BD = 12.5 cm (3 sf) [or 2 × root 39]
(BA)^2 + (AE)^2 = (BE)^2 [Pythagoras theorem]
39 + 9 = (BE)^2
BE = 6.93 cm (3 sf) [or 4 × root 3]