Question

I know this is like the 700th question I've asked​

Answer 1

Answer:

BC = 15

Step-by-step explanation:

Because of parallel lines, AD and BE, triangles ADC and BEC are similar.

In similar triangles, the lengths of corresponding sides are proportional.

AC/BC = DC/EC

We see that AC = AB + BC = 3 + BC

Also, DC = DE + EC = 2 + 10 = 12

(3 + BC)/BC = 12/10

(3 + BC)/BC = 6/5

Cross multiply.

5(3 + BC) = 6BC

15 + 5BC = 6BC

15 = BC

BC = 15