8th STAAR math translations, dilations, & angles

Trapezoid WKRP was translated 4 units to the left and 5 units up on a coordinate grid to create trapezoid WKRP ′′′ ′. Which rule describes this transformation?

• (x y, ) → (x − 4, y + 5)

• (x y, ) → (x + 4, y − 5)

• (x y, ) → (x + 4, y + 5)

• (x y, ) → (x − 4, y − 5)

Triangle TRW is shown on the coordinate grid to the left.

Triangle TRW will be dilated by a scale factor of n with the origin as the center of dilation to create triangle T R′ ′W′. Which ordered pair best represents the location of point R′?

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• ( 3− n, −5n)

• ( 3− + n, −5 + n)

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Triangle XYZ is rotated 90° clockwise about the origin to form triangle X Y′ ′Z′.

Which statement is true?

• The sum of the angle measures of triangle XYZ is 90° less than the sum of the angle measures of triangle X' Y′ Z' .

• The angle measures of triangle XYZ are less than the corresponding angle measures of triangle X' Y′ Z' .

• Triangle XYZ is not congruent to triangle X'Y′ Z' .

• The area of triangle XYZ is equal to the area of triangle X' Y′Z'

A transformation is applied to a figure to create a new figure on a coordinate grid. Which transformation does NOT preserve congruence?

• A rotation of 270° counterclockwise

• A reflection across the y-axis

• A dilation by a scale factor of 1.5

• A translation of 50 units down

Polygon LMNPQR is shown on the coordinate grid and models the shape of a garden in a park. Polygon LMNPQR will be dilated with the origin as the center of dilation to create polygon L 'M′′N′P′Q′R′. The vertex Q′ will be located at (21, 7).

Which rule best represents the dilation?

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• 
• 
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A figure was transformed on a coordinate grid using the rule ( x, y) → (− x, -y). Which of the following describes this transformation?

• A reflection across the x-axis

• A reflection across the y-axis

• A 90° clockwise rotation about the origin

• A 180° clockwise rotation about the origin

In each diagram, line g is parallel to line k, and line t intersects lines g and k.

Based on the diagrams, which statement about x is true?

• The value of x is 180, because the labeled angles in each diagram are supplementary and the sum of the measures of supplementary angles is 180 degrees.

• The value of x is 90, because the labeled angles in each diagram are complementary and the sum of the measures of complementary angles is 90 degrees.

• The value of x is 44, because the sum of the measures of the labeled angles in each diagram is 180 degrees.

• The value of x is 136, because the labeled angles in each diagram are congruent.

• 7.8 units

• 16.0 units

• 13.0 units

• 11.7 units

• 61 ft.

• 71 ft.

• 660 ft.

• 65 ft.