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The Unknown Side (Posted on 2002-07-01)

ABC is a triangle:

Angle A < 90.

D is a point on BC such that BD = DC.

M is a point on BC such that AM is perpendicular to BC.

AD = 10,

BC = 12 and

MC = 11
find the length of AC.

See The Solution Submitted by Dulanjana

Rating: 2.9091 (11 votes)

Comments: ( Back to comment list | You must be logged in to post comments.)

re: Trouble with the solution

| Comment 12 of 16 |

(In reply to Trouble with the solution by B)

Because, ABC is NOT a right triangle. The 3 sections of angle A are 21.7, 30, and 6.58 degrees. Add these up and you only have about 58 degrees, not 90.

You have 2 sides of right triangle ADM so you can find the 3rd side and the other 2 angles (30 & 60). Missing side is 8.66. You know MC is 11. Quadratic gives 13.99 for missing hypotnuse.

Done!

Posted by Jim on 2005-10-14 20:38:26

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