Question

Two angle of a quadrilateral are 89° and 113°. if the other two angle are equal, find the equal angle

Answer 1

89+113+2x=360
x=[360-202]÷2
79

Answer 2

let the equal angles be x 
∴89°+113°+x+x=360
∴89°+113°+2x=360
∴202+2x=360
∴2x=360-202
∴x=158
      the 2 equal angles are 158° & 158°