A square has a diagonal of length 5 cm. What is the area of the square?

Priya is teaching her younger cousin to ride a bike. She wants to stay on roads that are not too steep and easy enough for a new bike rider. She has decided the roads must have an angle less than or equal to 7 degrees. A 7-degree angle in a right triangle has a ratio for the legs. List the legs of 2 right triangles that would be safe for a new bike rider. 

Clare and Han are discussing how to find the unknown lengths. Clare says she is using similarity. Han says he is using the Pythagorean Theorem.

1. Do you agree with either of them? Show or explain your reasoning.
2. Find the unknown sides.

In right triangle , angle is a right angle, is 25 cm long, and is 24 cm long. What is the length of ?

Determine if each statement must be true, could possibly be true, or definitely can't be true. Explain or show your reasoning.

1. Isosceles triangles are similar. 
2. Equilateral triangles are similar.