I am struggling with triangles missing angles with the formula if you could explain your answer step by step that would be great. What is the formula for the isosceles triangle?
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Answer:
See below.
Step-by-step explanation:
The 3 angles of all triangles add up to 180 degrees.
An isosceles triangle has 2 of its angles equal.
So if one of the angles is 130 degrees then there cant be another one of 130 degrees as that would make 260 degrees.
So the other 2 angles are equal and their measure is (180 - 130) / 2
= 50 / 2
= 25 degrees.
The 2 equal angles are both 25 degrees.