There are three general rules that apply to the ACT:
1. No negative angles exist
2. No zero angles exist
3. You're extremly unlikely to see any fractional angles
-Angles that are greater than 0 but less than 90 degress are called acute angles
-Angles that are equal to 90 degress are called right angles
Secret: Don't automatically assume that angles that look like right angles are right angles. Without calculating the degree of the angle, you can't know for certain that an agle is a right angle unless one of the following is true
- The problem directly tells you "this is a right angle"
-You see a perpendicular symbol indicating that the lines form a 90 degree angle
-You see a box in the angle.