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Enlarge the triangle by scale factor 0.5 using (3, 1) as the centre of enlargement.

Enlarge the triangle by scale factor 0.5 using (3, 1) as the centre of enlargement-example-1

1 Answer

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Answer:

See attached

Explanation:

You want to dilate the given triangle by a factor of 0.5 centered on the point (3, 1).

Dilation

Each point of the image is half as far from (3, 1) as the original point is. For example, the points on the preimage that are 8 units to the left of (3, 1) will be 4 units to the left in the dilated image.

The dimensions of the dilated triangle will be 0.5 times those of the original.

The dilated triangle is shown in red in the attachment.

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Additional comment

It is often easiest to draw the dilated figure by counting grid squares on the graph. However, the coordinates can be computed using the transformation (for dilation factor k, center of dilation P) ...

(x, y) ⇒ (3, 1) +0.5((x, y) -(3, 1)) . . . . . . . . A ⇒ P +k(A -P) = kA +(1-k)P

(x, y) ⇒ (x+3, y+1)/2

For example,

(-5, -1) ⇒ (-5+3, -1+1)/2 = (-2, 0)/2 = (-1, 0)

Enlarge the triangle by scale factor 0.5 using (3, 1) as the centre of enlargement-example-1
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