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Question
If one angle of an isosceles triangle is 70°, then find the possibilities for the other two angles
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Solution
(i) Given one angle = 70°
Also, it is an isosceles triangle
Another angle also can be 70°
Sum of these two angles = 70° + 70° = 140°
We know that the sum of three angles in a triangle = 180°
Third angle = 180° – 140° = 40°
One possibility is 70°, 70° and 40°
(ii) Also if one angle is 70°
Sum of other two angles = 180° – 70° = 110°
Both are equal
They are `110/2` = 55°
Another possibility is 70°, 55° and 55°.
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