need help

 

What is KJL?     

 

Sides KJ and KL are equal (isoceles triangle).     

Since it's isoceles, angles KJL and KLJ are equal.     

 

The sum of all three angles of a triangle is 180^o.     

So the sum of KJL and KLJ is (180^o – 72^o) = 108^o     

 

Since KJL and KLJ are equal, each is half of 108^o.     

 

Therefore angle KJL is 54^o (i.e., half of 108^o).     

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