Question

in the adjoining figure observe the angels marked, and say if

Answer 1

In the given figure you can see ∠DCA = 70°

Also, ∠CAB = ∠CAE + ∠EAB = 25° + 45° = 70°

You can observe ∠CAB and ∠DCA  are opposite angles of transversal AC and both angle are equal ∴ we can say AB ║ CD (Alternate interior angles are equal)

Now,

∠AEF + ∠BAE = 135° + 45° = 180°

Also, observe that these two angles are on the same side of transvarsal AE,

∴ AB ║ EF ( Sum of adjacent angles or co-interior angles is 180°)