Answer
It is correct, if yo know that triangle is right-angled, you can find third angle if you know one acute angle. And only one side is all you need to find the other two sides if you know values of all angles.
Work Step by Step
1. Sum of angles in a triangle is $180^{\circ}$.
2. By sine, cosine or tangent, you can find any side if you know 1 side and one angle in right-angled triangle.
