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 answer:

B =  41.4096 °

Step-by-step explanation:

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°=41°2435"

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