Answer:
16
Step-by-step explanation:
If triangle GFE is similar to triangle RST, using the similarity theorem
RS/RT = GF/EF
Using pythagoras theorem;
RT² = 10² - 6²
RT² =100 - 36
RT² = 64
RT = √64
RT = 8
Recall that RS/RT = GF/EF
10/8 = 20/EF
Cross multiply
10EF = 8 * 20
10EF = 160
EF = 160/10
EF = 16
Hence the missing length is 16
