Isosceles triangle 10

In an isosceles triangle, the equal sides are 2/3 of the length of the base. Determine the measure of the base angles.

Correct result:

B =  41.4096 °

Solution:

a=c=23b cosB=b/2a cosB=b/223b cosB=1/223  B1=arccos(1/22/3)0.7227 rad  B=B1=B1 180π=0.7227 180π=41.41=41.4096=412435"

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