Question

What is the value of x? 15 20 60 180 An isosceles triangle with base angles labeled 60 degree and the other labeled open parenthesis 3 x closed parenthesis degree.

Answer 1

Remember that the sum of the interior angles of a triangle is always 180 degrees.  If the two base angles are 60 and 60 degrees respectively, that leaves 60 degrees for the the 3rd angle.  Let 60 degrees = 3x and find x.

x=20.

Check:  does 60 + 60 + 3(20) = 180?