We have that in the first one the dilation is a reduction and the scale factor is 1/2 with the scale factor we prove that the dilation is a reduction.
In the second one we have that the dilation is an enlargement and the sclae factor is 3 with the scale factor we prove that the dilation is an enlargement.
We can find the sacle factor with the next equation
you can take a side or the area of the figures and find the scale factor, for example in the first one we can do with one side od the triangle