Question

Triangle PQR is reflected across a line, P = (4,–5), and P’ = (–4, –5).

Answer 1

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Triangle PQR is reflected across a line, P = (4,–5), and P’ = (–4, –5).

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The y-axis.

It helps to draw it, or even imagine the point. If you want to look at just this point, you see 4,-5 became -4,-5. Since only the x-point changed, it reflected from the y-axis.