Answer:
17) 120°
18) 85°
Explanation:
→ Find the sum of angles in each shape
Quadrilateral = 360°
Triangle = 180°
→ Add the angles together and subtract it from the sum
360 - ( 80 + 80 + 80 ) = 120° for number 17
180 - ( 35 + 60 ) = 85° for number 18