∣z−1∣≤1⇒∣(x−1)+iy∣≤1∣⇒(x−1)2+y2≤1⇒(x−1)2+y2≤1…(1) Also ∣z−5∣≤∣z−5i∣(x−5)2+y2≤x2+(y−5)2−10x≤−10y⇒x≥y.....(2) Solving (1) and (2) ⇒(x−1)2+x2=1⇒2x2−2x=0⇒x(x−1)=0⇒x=0 or x=1y=0 or y=1 
Given x,y∈I Points (0,0),(1,0),(2,0),(1,1),(1,−1) to find $\begin{aligned}
& \left|z_1\right|^2+\left|z_2\right|^2+\left|z_3\right|^2+\left|z_4\right|^2+\left|z_5\right|^2 \
& =0+1+4+1+1+1+1=9
\end{aligned}$