Answer:
a. the lengths of all three sides of a triangle
Explanation:
To find the measure of an interior angle, you need to know three sides of the triangle.
Let me explain with the cosine formula.
c^2 = a^2 + b^2 -2ab cos C
Here a, b, c are the sides of the triangle and C is an interior angle.
Form the above formula, we can find C.
cos C = (a^2 + b^2 - c^2)/2ab
Therefore, we need three sides to find an interior angle using the cosine formula.
Hope this will helpful.
Thank you.