Posted by Melania on .
I'm stuck!! Can someone please help me with this problem??
A triangle has vertices (1, 4), (1, 1), and (3, 1). The triangle is dilated by a scale factor of 2, then translated 5 units up, and then rotated 90 degrees counterclockwise about the origin. What are the vertices of the image of the triangle?

Algebra 
Steve,
dilate by 2: (x,y) > (2x,2y)
up 5: (x,y) > (x,y+5)
rotate: (x,y) > (y,x)
combining them,
(x,y) > (2x,2y) > (2x,2y+5) > ((2y+5),2x)
so,
(1,4) > (13,2)
and so on for the other points