Question

Which angle's measure is equal to the sum of the measures

of ZBAC and ZBCA?
ZCBA
ZCBE
O ZDAC
ZBCF

Answer 1

∠ BAC + ∠ BCA = ∠ CBE

Explanation:

See the attached diagram of the triangle.

We know from the property of angles of a triangle, the sum of any two interior angles is always equal to the opposite exterior angle.

Now, ∠ BAC and ∠ BCA are two interior angles of Δ ABC. Therefore, the opposite exterior angle is ∠ CBE.

Hence, ∠ BAC + ∠ BCA = ∠ CBE (Answer)