how to finder this angle?
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Answer:
two other angles of a triangle are 75 degree .Both two angles will be 70 degree since it is an isosceles triangle.
Step-by-step explanation:
according to the given diagram the given triangle is an isoscels triangle because it's to sides are equal
here unknown name is also c degree because the base angles of an isosceles triangle are equal.
so to find angle c
equation is :
c + c + 30 = 180 degree (sum of interior angles of a triangle)
2c + 30 = 180
2c = 180 - 30
2c = 150
c = 75 degree