Answer
$X[-20,110,10]$ by $Y[-10,60,10]$
Work Step by Step
1. Examine the given coordinates, we can find the minimum and maximum of each direction as $X, -10, 100$ and $Y, -1, 50$
2. Set scale=10 and the window 10 unit larger each direction to cover the above numbers, we can get the viewing window as $X[-20,110,10]$ by $Y[-10,60,10]$ where the first number in the bracket represents the minimum value, the second number the maximum value, and the last number the scale.