Kelsey needs to reflect ∆DEF across the line y = x. If she drew the image ∆D'E'F', shown below, did Kelsey correctly reflect ∆DEF across the line y = x?

your answer is the frist one

hop i

cross multiplying, we get :

⇒ (3) × (5) = (9) × (x)

⇒ 15 = 9x

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