Question
Mathematics Question on Angle Sum Property Of A Triangle
Find the value of the unknown x in the following diagrams:
Answer
The sum of all interior angles of a triangle is 180°. By using this property, these problems can be solved as follows.
(i) x+50°+60°
= 180°x+110°=180°x
= 180°−110°=70°
(ii) x+90°+30°
= 180°x+120° =180°x
= 180°−120°
=60°
(iii) x+30°+110°=180°x+140°=180°
x=180°−140°=40°
(iv) 50°+x+x=180°
50°+2x=180°
2x=180°−50°=130°
x=2130∘=65∘
(v) x+x+x=180°
3x=180°
x=3180=60∘
(vi) x+2x+90°=180°
3x=180°−90°=90º
x=390∘=30∘