Parallel lines in shapes can form corresponding and alternate angles. You can use these properties to find missing angles. Part of Maths Angle, symmetry and transformation ...

Key fact The sum of interior angles in a triangle is 180°. To prove \ (a + b + c = 180^\circ\), firstly draw a line parallel to one side of the triangle. \ (d = b\) (alternate angles are equal) ...

(iii) any one pair of interior angles on the same side of the transversal is supplementary, then the lines are parallel. • Lines which are parallel to a given line are parallel to each other.

Answer: None Sum of given angles = 47° + 70° + 85° = 202° ≠ 180°. Since the sum of all three angles is not equal to 180°. So, no triangle can be drawn with the given angles. 5.