Let the other point be (x,y)

Now, mid-point of (x,y) &(0,5) will be

[{(x+0)/2},{(y+5)/2}]

Given

{(x+0)/2} = 0

thus, x = 0

Also,

{(y+5)/2} = -3

or, y + 5 = -6

or, y = -11

Hence the required point (x,y) is (0,-11)

Let the other point be (x,y)

Now, mid-point of (x,y) &(0,5) will be

[{(x+0)/2},{(y+5)/2}]

Given

{(x+0)/2} = 0

thus, x = 0

Also,

{(y+5)/2} = -3

or, y + 5 = -6

or, y = -11

Hence the required point (x,y) is (0,-11)