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All Comments (6)
Puscasu Emanuel 1 year ago
An easier way (I paused the video before Sal started solving) was to find BE first (BEA - 30/60/90 triangle), then find BD(same as above, this time in the BDC triangle). You then notice that the measure of angle BDE is 30 (complementary angle) which is the same as DBE (trisector).
From these you can see that BDE is an isosceles triangle so EB = DE. After this you simply calculate the perimeter as usual.
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Peter Mouse 1 year ago
easy
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Dror Ben Ami 1 year ago
no way, this is 9th grade math in the USA, possibly even tenth
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2SeeriusMusic 1 year ago
Nice memory refresher...I think this was Grade 6
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