Question

If the angles of a quadrilateral are x°, (x – 20)°, (x – 30)° and (x + 10)° find x.

Answer 1

Sum of angles of quadrilateral is 360 degree.

x°+ (x – 20)°+(x – 30)° + (x + 10)°= 360°

x°+x – 20°+x – 30° + x + 10°= 360°

x°+x°+x°+x°– 20°– 30°+ 10°= 360°

4x°-40=360°

4x°= 360°+40°=400°

x=400/4°=100°

The angles = x°=100°, (x – 20)°=100-20°=80°,

x – 30°=100-30=70°, x + 10°= 100+10°=110° answer.