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

What is the scale factor of the dilation?

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$\text{Basic}$
$x$$y$$x^2$$\sqrt{ }$$\frac{x}{ }$
$x\frac{ }{ }$
$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).