Theorem 8.5 : If in a quadrilateral, each pair of opposite angles is equal, then it is a parallelogram.
Text Solution
Verified by Experts
By angle sum property of quadrilateral
`/_1+/_2+/_3+/_4=360`
`/_1+/_2+/_1+/_2=360`
`2(/_1+/_2)=360`
`/_1+/_2=180`
For lines `AD` and `BC` with `AB` as transversal,
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