(X/4)^2+(5-X/4)^2=17
(X/4)^2+(X/4)^2-5X/2+25=17
2(X/4)^2-5X/2+8=0
(X/4)^2-5X/4+4=0
(X/4)^2-5X/4+25/4+4-25/4=0
(X/4-5/2)^2=9/4
X/4-5/2=正负3/2
x=16或者x=4