Question

in given fig.abcd is a square, find x

Answer 1

Since diagonal bisects the vertex of a square,

anOCE = anOCD = 45

anDOA + anAOE = 180

anDOA = 180 - 120 = 60

anDOA = anCOE = 60.  (vertically opposite)

In triangle COE

anOCE + anCOE + x = 180

x = 180 - 45 - 60

x = 75

Answer 2

Answer

Angle DOC=120°(vertically opposite angle)

Angle DOC+angleCOE= 180° (Linear pair)

AngleCOE=60°

Similarly, angleDOA=60°

angle DOA= angleOCE (alternative interior angle)

angleOCE=60°

angleCOE+angleOCE+x=180(angle sum property of triangle)

60°+60°+x=180°

120°+x=180°

x=180°-120°

x=60°