The smaller triangle is the image of the larger triangle after a dilation. the center of the dilation is (4,2).

two triangles are graphed on a coordinate plane. the horizontal x-axis ranges from negative 10 to 10 in increments of 1. the vertical y-axis ranges from negative 10 to 10 in increments of 1. a dashed triangle has vertices at begin ordered pair 4 comma 2 end ordered pair, begin ordered pair 4 comma 5 end ordered pair, and begin ordered pair 8 comma 2 end ordered pair. a solid triangle has vertices at begin ordered pair 4 comma 2 end ordered pair, begin ordered pair negative 8 comma 2 end ordered pair, and begin ordered pair 4 comma negative 7 end ordered pair.

what is the scale factor used to create the dilation?

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