Follow the instructions on the image

k=3

Step-by-step explanation:

Assuming the centre of dilation is 0,0, we can use the formula (kx,ky) to determine it.

Here,

The co-ordinates of pre-image=(0,1),(-1,-1) & (1,-1)

The co-ordinates of image=(0,3),(-3,-3) & (3,-3)

Now,

(kx,ky)=(0,3)

(k*0,k*1)=(0,3)

Equating,

k=3

You can use the other coordinates to further solidify your answer.

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