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WRITING Explain why a scale factor of 2 is the same as 200%

Solve the equation. $$-2(8-y)=-6 y$$

Last year, the track team's yard sale earned \(\$ 500 .\) This year, the yard sale earned \(\$ 625 .\) What is the percent of increase?

ATTENDING TO PRECISION You are making a blueprint of your house. You measure the lengths of the walls of your room to be 11 feet by 12 feet. When you draw your room on the blueprint, the lengths of the walls are 8.25 inches by 9 inches. What scale factor dilates your room to the blueprint?

MAKING AN ARGUMENT Your friend claims that dilating a \(\square\)gure by 1 is the same as dilating a \(\square\)gure by \(?1\) because the original \(\square\)gure will not be enlarged or reduced. Is your friend correct? Explain your reasoning.

USING STRUCTURE Rectangle WXYZhas vertices \(\mathrm{W}(-3,-1), \mathrm{X}(-3,3), \mathrm{Y}(5,3),\) and \(\mathrm{Z}(5,-1)\) a. Find the perimeter and area of the rectangle.b. Dilate the rectangle using a scale factor of 3. Find the perimeter and area of the dilated rectangle. Compare with the original rectangle. What do you notice? c. Repeat part (b) using a scale factor of \(\frac{1}{4}\) . d. Make a conjecture for how the perimeter and area change when a \(\square\)gure is dilated.

REASONING \(\delta \)ABC has vertices \(\mathrm{A}(4,2), \mathrm{B}(4,6),\) and \(\mathrm{C}(7,2)\) . Find the coordinates of the vertices of the image after a dilation with center \((4,0)\) and a scale factor of \(2 .\)