Respuesta :
Answer: [tex]D'(-14,1);\ E'(4,7);\ F'(4,1)[/tex]
Step-by-step explanation:
Since the center of dilation is not at the origin, we can use the following formula in order to find the coordinates of the vertices of the triangle D'E'F':
[tex]D_{O,k}(x,y)=(k(x-a)+a, k(y-b)+b)[/tex]
Where "O" is the center of dilation at (a,b) and "k" is the scale factor.
In this case you can identify that:
[tex](a,b)=(1,1)\\k=3[/tex]
Therefore, susbtituting values into the formula shown above, you get that the coordinates ot the resulting triangle D'E'F, are the following:
Vertex D' → [tex](3(-4-1)+1,\ 3(1-1)+1)=(-14,1)[/tex]
Vertex E' → [tex](3(2-1)+1,\ 3(3-1)+1)=(4,7)[/tex]
Vertex F' → [tex](3(2-1)+1,\ 3(1-1)+1)=(4,1)[/tex]