Answer:
a) XY and BD are paralel and they are on the same side in relation to AB line
b) Lines XB and XC have the same size and are supported by the same line BC, therefore XBC and XCB have the same angles, therefore XCB is also 55º.
The sum of all angles of a triangle is 180 so BXC is 180 - 55 - 55.
180 - 110 = 70º
BXC = 70º... probably
Explanation: