C: <span>a triangle that must have the same dimensions as the bases</span>
Im not 100 percent positive that this is correct but I think the answer is
184
Answer:

Step-by-step explanation:
Find out what half of 39° (angle ABD) Then subtract that from 180° (angle ABE). When the plain flus faster angle (ABD) gets smaller and angle (ABE) gets bigger. Hope that helps.