# If ABCD is a cyclic quadrilateral with ∠A=50o, ∠B=80o, then ∠C and ∠D are :

- 115
^{o}, 115^{o} - 110
^{o},120^{o} - 130
^{o}, 100^{o} - 100
^{o}, 130^{o}

**Answer is 100 degree and 130 degree**

**Explanation:-**

As we know that the sum of adjacent angle is 180 degree.

Then, Angle B + Angle C = 180 degree

80 degree + Angle C = 180 degree

Angle C = 180 – 80

**Angle C = 100 degree**

And Angle A + Angle D = 180 degree

50 degree + Angle D = 180 degree

Angle D = 180 – 50

Angle D = 130 degree

Then, the value of Angle C and Angle D are 100 degree & 130 degree.

Hence, the correct answer is option (4) 100 degree and 130 degree.