Answer:
155°
Explanation:
The total of the angles in a triangle is 180° and also any pair or trio of angles that maje a straight angle also add up to 180°. So look for those set ups.
The left most triangle has an angle marked 35° and also a right angle is labelled. The right angle is 90° So the third angle must be 180° - (35°+90°)
180° - 125°
55°
The 55° angle(we just found) and the 60° angle (labelled) and a third unmarked angle all together maje a straight angle, 180°.
So we can calculate the third angle, which is an angle in the other shown triangle.
180° - (55° + 60°)
180° - 115°
65°
This triangle also has a right angle in it. And the third angle can be calculated in the same way.
180° - (65° + 90°)
180° - 155°
25°
Last time, the 25° angle and the angle marked x make a straight angle.
180° - 25°
155°