Perimeter and Area with Scale Factors

A triangle has an area of 6 square inches and a perimeter of 12 inches. Suppose it is dilated by some scale factor, and the area and perimeter of the image are calculated. Match each graph with the relationship it represents.

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If two similar figures have a perimeter ratio of 4:5, then what is the ratio of the area?

• 4:5

• 8:10

• 16:25

• 16:10

If two similar figures have a perimeter ratio of 4:5, then what is the scale factor?

• 4:5

• 16:25

• 8:10

• 2:2.5

If two similar figures have an area ratio of 100:81, then what is their perimeter ratio?

• 100:81

• 10:9

• 50:40.5

• 5:9

What do you have to do to the perimeter ratio or scale factor to get the area ratio?

• divide by 2

• square the ratio

• square root the ratio

• nothing, it is the same value

True or false? Perimeter ratios and scale factors have the same value.

• true

• false

The number multiplied by x and y to result in a dilation is called the ______.

• Scale Factor

• Exponent

• Coefficient

• Variable

A scale factor greater than one creates ....

• reduction

• enlargement

• exact copy

• none of these

A square with an area of 16 square inches has been dilated to a square with an area of 64 square inches. What is the scale factor of the dilation?

• k = 1/2

• k = 1/4

• k = 2

• k = 4