Answer:
m = 8
Explanation:
As we can see we have two similar triangles
These are triangles FDH and GEF
mathematically, when two triangles are similar, the ratio of their corresponding sides are equal;
Thus;
DH/DF = EG/EF
12/15 = m/10
15 * m = 12 * 10
15 m = 120
m = 120/15
m = 8