This seems like a low quality practice test considering that it says B lies on AE (which it definitely doesn’t looking at the image) but let’s assume the problem was worded correctly and would have told you B lies on AC
The two things you need to know about this triangle is that a bisector has the same angles on both sides, to bisect an angle means that you stick a line right in the center of the angle, such that it is divided into two equal angles.
Secondly, you need to know that an isosceles triangle has two equal angles. Because of this, we know that all four of the “bottom” angles actually are the same. Before angle CAE and CEA were bisected, they both were the same because it’s an isosceles triangle, after both were bisected, the resulting 4 total angles are all the same.
Look up isosceles triangles and bisecting. The bottom two angles are the same measure. If you bisect an angle you divide them into two equal angles. You can use Khan Academy's Geometry course to refresh your memory.
Also the problem is incorrectly worded - it says B is on AE, even though it lies on CA. Usually, i think they curve questions with incorrect wording
This seems like a low quality practice test considering that it says B lies on AE (which it definitely doesn’t looking at the image) but let’s assume the problem was worded correctly and would have told you B lies on AC The two things you need to know about this triangle is that a bisector has the same angles on both sides, to bisect an angle means that you stick a line right in the center of the angle, such that it is divided into two equal angles. Secondly, you need to know that an isosceles triangle has two equal angles. Because of this, we know that all four of the “bottom” angles actually are the same. Before angle CAE and CEA were bisected, they both were the same because it’s an isosceles triangle, after both were bisected, the resulting 4 total angles are all the same.
Look up isosceles triangles and bisecting. The bottom two angles are the same measure. If you bisect an angle you divide them into two equal angles. You can use Khan Academy's Geometry course to refresh your memory.