Answer:
since angle 1 and angle 2 are equal both angles can only be 90.
and given that b is perpendicular to d so angle at point of interception of bd is also 90.
it is also given that c and d are parallel so both line have same angle on point of interception of line a and b and angle formed is also the same on line a and b .....so a and b are parallell
Step-by-step explanation: