Question

Which description is true about ​pre-image ABC​ and ​image A′B′C′​ ?

A.) The image is a rotation of the pre-image clockwise at 90°.

B.) The image is a reflection of the pre-image across the y-axis.

C.) The image is a dilation of the pre-image with a scale factor or 3.

D.) The image is a translation of the pre-image by moving up 2 units and to the right 2 units.

Answer 1

Option (C)

Explanation:

From the graph attached,

In ΔABC and ΔA'B'C',

∠A ≅ ∠A'

∠B ≅ ∠B'

Therefore, ΔABC ~ ΔA'B'C'

Corresponding sides of these triangles will be proportional.

`\frac{\text{AB}}{\text{A'B'}}=\frac{\text{BC}}{\text{B'C'}}=\frac{\text{AC}}{\text{A'C'}}=(2)/(6)`

Therefore, ratio of the sides, AC : A'C' = 1 : 3 shows that image triangle A'B'C' is a dilated form of pre-image ABC with a scale factor of 3.

Option (C) will be the correct option.