Question

Prove the sum of four angles of a quadrilateral =360°

Answer 1

Answer:

Step-by-step explanation:

A Quadrilateral has 4 angles

1st angle =90 degree

2nd angle =90 degree

3rd angle =90 degree

4th angle =90 degree

Answer 2

Answer:

To prove : A+B +C+D = 360°

Sol: According to Fig Quadrilateral is divided into 2 triangle

ABD and BDC

Now ,In ABD ,By angle sum property of triangle

A + 1 +3 = 180° -------(1)

In BDC ,By angle sum property of triangle

C+ 2 +4 = 180° -------(2)

Add equation (1) and (2)

A + 1 +3+C+ 2 +4 = 180° + 180°

A+ 1 +2+ C+ 3+4 = 180°+1 80°A+ B +C +D = 360° (From the figure B=1 +2 and D=3+4)

Hence Proved