How can I find the centre of Enlargement ?

Question

When I draw a triangle and then enlarge it with a scale of what ever : How can I find the centre of enlargement of those 2 Triangles ? Thank you

Answer 1

Draw Δ ABC and Δ A` B` C`
Δ A` B` C` is enlarged triangle.

Draw lines A` A produced , B` B produced and C` C produced.
Lines meet at centre of enlargement.

Answer 2

draw lines connecting each vertex in the original triangle with the corresponding vertex in the image. the lines will be concurrent at the center of dilation.