Dilation Review

Triangle CAT is formed by dilating triangle DOG. Which of the following is true?

A rectangular tin sign comes in three sizes, small, medium and large. All three have similar shapes. If the sides of the smallest sign are tripled to create the largest sign, which statement is true.

• The area of the largest sign is three times the area of the smaller sign.

• The perimeter of the larger sign is nine times the perimeter of the smaller sign.

• The perimeter of the larger sign is three times the perimeter of the smaller sign.

• The area of the smaller sign is nine times the area of the larger sign.

Which transformation des NOT preserve congruence?

• (x,y) -> (x,-y)

• (x,y) -> (4x, 4y)

• (x, y) -> (x+4, y-1)

• (x,y) -> (y, -x)

Triangle ABC has coordinates A(2,8), B (4,6), C (6, -4). If ABC is dilated with the origin as the center of dilation to create triangle A'B'C', with coordinates A' (1,4), B'(2,3), and C'(3,-2), what is the rule of the dilation?

• (x,y) -> (2x, 2y)

• (x,y) -> x-1, y-4)

• If a< 1, then the image of XYZ is larger than the pre-image.

• If a > 1, then the image of XYZ is smaller than the pre-image.

• If a= 1, then the image of XYZ is larger than the pre-image.

• If a< 1, then the image of XYZ is smaller than the pre-image.

Rectangle GHJK has coordinates (4, -2), (4,3), (2, -2) and (2,3). If GHJK is dilated with a scale factor of 7, which of the following coordinates could be from rectangle G'H'J'K'?

• (28, -28)

• (4, 21)

• (14, -14)

• (9, 10)

• The angle measures of ABC are less than than the angle measures of triangle A'B'C'.

• The angle measures of A'B'C' are less than the angle measures of ABC.

Pentagon ABCDE is dilated to form A'B'C'D'E' using the rule (x,y) -> (3x, 3y) . Match each pre-image point with the corresponding point on the image.

• (9,3)

• (2, -4)

• (-12, 6)

• (-4,2)

• (6, -12)

• (3,-1)

• (-9,3)

• (-3,1)

• (9, -3)

• (3,1)