<u><em>Answer:</em></u>
AE = 9 units
<u><em>Explanation:</em></u>
We know that the line joining two midpoints in a triangle is parallel to the third side and equals half its length
<u>In the diagram, we are given that:</u>
segment BD // segment AE and that segment BD is a mid-segment of the ΔACE
<u>According the above theorem, we can conclude that:</u>
BD = 0.5 × AE ......................> I
<u>1- getting the length of BD:</u>
<u>Length of segment BD can be calculated using the distance formula:</u>

<u>We are given that:</u>
B is at (3.5,1.5) which means that x₁ = 3.5 and y₁=1.5
D is at (-1,1.5) which means that x₂=-1 and y₂=1.5
<u>Substitute in the formula:</u>
units
<u>2- getting the length of AE:</u>
<u>using equation I:</u>
BD = 0.5 × AE
4.5 = 0.5 × AE
AE = 2 × 4.5
AE = 9 units
Hope this helps :)