SOLUTION: Triangle FEC is equilateral with a side length of 20cm and FE tangent to the circle at F. Find the length of chord FA if ED = 8cm. https://media.discordapp.net/attachments/7230

Algebra ->  Length-and-distance -> SOLUTION: Triangle FEC is equilateral with a side length of 20cm and FE tangent to the circle at F. Find the length of chord FA if ED = 8cm. https://media.discordapp.net/attachments/7230      Log On


   



Question 1181244: Triangle FEC is equilateral with a side
length of 20cm and FE tangent to
the circle at F. Find the length of
chord FA if ED = 8cm.
https://media.discordapp.net/attachments/723023718497910816/849268983684399124/unknown.png?width=155&height=135

Answer by Edwin McCravy(20056) About Me  (Show Source):
You can put this solution on YOUR website!



FE%5E2%22%22=%22%22ED%2AEB  tangent-secant theorem

FE%5E2%22%22=%22%22ED%2A%28ED%2BDB%29
20%5E2%22%22=%22%228%2A%288%2BDB%29
400%22%22=%22%228%2A%288%2BDB%29
50%22%22=%22%228%2BDB
42%22%22=%22%22DB

CB%22%22=%22%22DB-DC
CB%22%22=%22%2242-12
CB%22%22=%22%2230

DC%2ACB%22%22=%22%22FC%2ACA  intersecting chords theorem
12%2A30%22%22=%22%2220%2ACA
360%22%22=%22%2220%2ACA
18%22%22=%22%22CA

Chord FA%22%22=%22%22FC+%2B+CA%22%22=%22%2220%2B18%22%22=%22%2238

Edwin