A triangle has vertices with coordinates (2, 0), (3, -1), and (-2, -5). If the triangle is dilated by a scale factor of 3 with the origin as the center of dilation, what are the coordinates of the vertices of the image.

Question

A triangle has vertices with coordinates (2, 0), (3, -1), and (-2, -5).  If the triangle is dilated by a scale factor of 3 with the origin as the center of dilation, what are the coordinates of the vertices of the image.

Reiny · Accepted Answer

If the scale factor is 3, then

A(2,0) ----> A' (6,0)
B(3,-1) ---> B' (9,-3)
C(-2,-5) --> C' (-6,-15)

Can't get any simpler than that.

Might be a good idea to graph the original triangle and the new triangle.
What do you notice ?

todd · Answer

The vertices of triangle ABC are A(3, -6), B(6,3), C(9,-3). Find the image matrix that represents the dilation of triangle ABC centered at the origin with a scale factor of 2/3. Then graph the triangle and its image