Answer:
a=18.7 or 19 rounded up
Step-by-step explanation:
Use Pythagoras Thereom
a^2=8^2+17^2
a^2=64+289
a^2=353
√353
a=18
The length of missing leg is 15 cm.
b is the correct answer
see the step in the picture
x= 6
∠FGT = 55
∠GFE = 65