Triangle Angles A0B289
1. **State the problem:** We need to find the measures of angles 1, 2, 3, and 4 in a right triangle where angle 2 is given as 35° and the right angle is at the bottom left corner.
2. **Recall important rules:**
- The sum of angles in any triangle is 180°.
- A right angle measures 90°.
- Adjacent angles on a straight line sum to 180°.
3. **Given:**
- $m\angle 2 = 35^\circ$
- $m\angle 3 = 90^\circ$ (right angle)
4. **Find $m\angle 1$:**
Since angles 1, 2, and 3 are the three angles of the triangle,
$$m\angle 1 + m\angle 2 + m\angle 3 = 180^\circ$$
Substitute known values:
$$m\angle 1 + 35^\circ + 90^\circ = 180^\circ$$
Simplify:
$$m\angle 1 + 125^\circ = 180^\circ$$
Subtract 125° from both sides:
$$m\angle 1 = 180^\circ - 125^\circ = 55^\circ$$
5. **Find $m\angle 4$:**
Angle 4 is adjacent to angle 3 on a straight line, so:
$$m\angle 3 + m\angle 4 = 180^\circ$$
Substitute $m\angle 3 = 90^\circ$:
$$90^\circ + m\angle 4 = 180^\circ$$
Subtract 90° from both sides:
$$m\angle 4 = 90^\circ$$
**Final answers:**
$$m\angle 1 = 55^\circ, \quad m\angle 2 = 35^\circ, \quad m\angle 3 = 90^\circ, \quad m\angle 4 = 90^\circ$$