Chapter 14 Quadrilaterals R.D. Sharma Solutions for Class 9th Exercise 14.1
Exercise 14.1
1. Three angles of a quadrilateral are respectively equal to 110°, 50° and 40°. Find its fourth angles.
Solution
2. In a quadrilateral ABCD, the angles A, B, C and D are in the ratio 1 : 2 : 4 : 5. Find the measure of each angles of the quadrilateral.
Solution
Solution
4. The angles of quadrilateral are in ratio 3:5:9:13. Find all angles of the quadrilateral.
Solution:
We know that sum of all angles of a triangle is 360°
It is given; angles are in ratio 3:5:9:13. So, we can say, the angles are 3x, 5x, 9x and 13x.
Sum of all angles
3x+5x+9x+13x = 360°
⇒30x=360°
⇒x = 360°/30 = 12°
So, angles are
3x = 3×12°=36°
5x = 5×12°=60°
9x =9×12°= 108°
13x =13×12°=156°
So, angles are 36°, 60°,108°, 156°