answer: the proof is mentioned below.
step-by-step explanation:
since, given: lines bc = ef
prove: lines ac > ef
statements reason
1. bc=ef 1. given
2. ac= ab+bc 2. because b is the point between the
line segment ac
3. ac > bc 3. because if a line segment is equal to
the sum of two line segments then it is
always greater then each of these
individual line segments
4. ac > ef 4. by equality property.