To shift a circle 2 units to the right and 3 units up, we need to adjust the coordinates of its center accordingly.
The original center is (5, -6). To shift it 2 units to the right, we add 2 to the x-coordinate, resulting in a new x-coordinate of 5 + 2 = 7. To shift it 3 units up, we add 3 to the y-coordinate, giving us a new y-coordinate of -6 + 3 = -3.
Therefore, the new center of the shifted circle is (7, -3).
Now let's examine the answer options to see which one represents the shifted circle correctly.
Option 1: (x-3)^2+(y+9)^2=1
This option does not shift the circle correctly, as the x-coordinate of the center is shifted to the left instead of 2 units to the right.
Option 2: (x-7)^2+(y+9)^2=1
This option correctly shifts the circle 2 units to the right, as the x-coordinate of the center is now 7. However, it does not shift the circle 3 units up, as the y-coordinate of the center is still 9 units above the original center.
Option 3: (x+2)^2+(y+3)^2=1
This option does not shift the circle correctly, as the new center is shifted 2 units to the left instead of 2 units to the right.
Option 4: (x-2)^2+(y-3)^2=1
This option correctly shifts the circle 2 units to the right, as the x-coordinate of the center is now 2. It also correctly shifts the circle 3 units up, as the y-coordinate of the center is now -3.
Therefore, the correct answer is option 4: (x-2)^2+(y-3)^2=1.