Rectangle A′B′C′D′ is the image of rectangle ABCD after a dilation.

What is the scale factor of the dilation?

Enter your answer in the box.

$text{Basic}$

$x$$y$$x^2$$sqrt{ }$$frac{x}{ }$

$xfrac{ }{ }$

$x^{ }$$x_{ }$$degree$$left(right)$$abs{ }$$pi$$infty$

A coordinate plane that includes two rectangles rectangle ABCD and rectangle A prime B prime C prime D prime. For rectangle ABCD, point A is at (1, 5), point B is at (4, 5), point C is at (4, 1), and point D is at (1, 1). For rectangle A prime B prime C prime D prime, point A prime is at (3, 15), point B prime is at (12, 15), point C prime is at (12, 3), and point D prime is at (3, 3).