Triangle abc has vertices a(5, 3) , b(3, 7) , and c(1, 4) . triangle abc is dilated, and the vertices of the image are a′(1.25, 0.75) , b′(0.75, 1.75) , and c′(0.25, 1) . the center of dilation is the origin. what is the scale factor of the dilation? 0.25 0.5 2 4

FFirst, we have the following points:
 A (5, 3) 
 B (3, 7) 
 C (1, 4) 
 We multiply these vertices by a factor k to obtain the new vertices: 
 A '(k * 5, k * 3) = (1.25, 0.75) 
 B '(k * 3, k * 7) = (0.75, 1.75) 
 C '(k * 1, k * 4) = (0.25, 1)
 We note that the value of k is: k = 1/4
 
 the scale factor of the dilation is:
 0.25

Using the rise/run rule. you would get 2/6.simp. 1/3