Lesson 15

In triangle \(ABC\), the measure of angle \(A\) is \(40^\circ\).

1. Give possible measures for angles \(B\) and \(C\) if triangle \(ABC\) is isosceles.
2. Give possible measures for angles \(B\) and \(C\) if triangle \(ABC\) is right.

For each set of angles, decide if there is a triangle whose angles have these measures in degrees:

1. 60, 60, 60
2. 90, 90, 45
3. 30, 40, 50
4. 90, 45, 45
5. 120, 30, 30

If you get stuck, consider making a line segment. Then use a protractor to measure angles with the first two angle measures.

Angle \(A\) in triangle \(ABC\) is obtuse. Can angle \(B\) or angle \(C\) be obtuse? Explain your reasoning.

For each pair of polygons, describe the transformation that could be applied to Polygon A to get Polygon B.

On the grid, draw a scaled copy of quadrilateral \(ABCD\) using a scale factor of \(\frac12\).