The y-coordinate of point j' in the image triangle J'K'L' is **-x coordinate** of point j in the initial triangle JKL.

**Step-by-step explanation:**

The rule to apply here is that of 90° clockwise about the origin.

This is to say that: rotation 270° counterclockwise about the origin applies the same rule as rotation 90° clockwise about the origin.

In this case, If point j has coordinates (x,y) then after the rotation j' will have coordinates (y,-x)

So the y-coordinate of point j' in the image triangle J'K'L' is **-x coordinate** of point j in the initial triangle JKL.

**Learn more**

Rotation about the origin 270°:brainly.com/question/3382538

Keywords : triangle, rotated, origin, counterclockwise,y-coordinate

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