In an isoceles triangle, the 2 bottom angles (in this case is angle bad and bcd) are equal.
Triangle DBA and DBC both have 2 equal angles (a right angle, and the bottom angles - property)
So, their third angle must also be equal to each other (cause 3 add up to 180, and since the sum of the first 2 are equal, the third one must also be.)
Answer: you need a x and y axis to get this answer
Step-by-step explanation: first you put the (3,5) and (3,-7) in a graph paper then make an y and x axis and you will be able to see your answer visually