Answer is E
Here's a rough version of the image.
Statement 1 is insufficient.
We know angle x is 70, but we know nothing about the placement of point D. The lower the placement of point D the greater the angle y, so y could really be any number of values. Remember we can't assume anything about the placement of a point, unless we are explicitly told about the placement in the question.
Statement 2 is insufficient.
x and y could be any number of values. For instance x could be 50 degrees or 70 degrees. All we know is that the triangles are isosceles, but we know nothing about the angles.
Statements 1 and 2 together are insufficient.
From statement 1 we know x is 70 and that angles BAC and BCA are both 55. But again we know nothing about the placement of point D. Point D could be very close to B in which case y would be close to 70 degrees or point D could be close to the segment AC in which case y would be close to 180 degrees.
I hope that helps!
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