Answer:
x is 40.
Explanation:
The triangle with all sides equal is an equilateral triangle, one you shouldn't be bothered about. This is because the angle of 100 has already been given. If you look at the diagram closely, you can see that the triangle in which angle x is present is an isosceles triangle. Since the top angle is already given, there is a formula to calculate the bottom angle, i.e., x.
The formula is : (180- the top angle, in this case 100) / 2
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