Back to Use rigid motions for congruence — Problem 5 · Task Set 6

Exercises: Use Rigid Motions to Define and Determine Congruence

Work through each section in order. For problems that ask you to find a rigid motion,
verify your answer by checking every vertex.

Grade 9·20 problems·~30 min·Common Core Math - HS Geometry·standard·hsg-co-b-6

Work through problems with immediate feedback

Fluency Practice

Apply rigid motions and the definition of congruence to answer each problem.

Triangle $DEF$ has vertices $D(-1, -1)$ , $E(-4, -1)$ , and $F(-2, -4)$ .
Triangle $GHI$ has vertices $G(1, 1)$ , $H(4, 1)$ , and $I(2, 4)$ .
Which single rigid motion maps $\triangle DEF$ onto $\triangle GHI$ ?

A translation by $\langle 2, 2 \rangle$

A $180^\circ$ rotation about the origin

A reflection over the $y$ -axis

A reflection over the line $y = x$