Changing Dimensions Proportionally

If a rectangle is drawn and another rectangle is drawn so that the sides are twice as big as the first rectangle, what happens to the area?

• doubles
• triples
• quadruples
• not enough information

What happens to the perimeter of a square if the sides are    halved?

• doubles
• halved
• quadrupled
• forthed

What is Dilation?

• Dilation means to enlarge or reduce
• Dilation means to reflect on something
• Dilation means to like something
• Dilation means to make something different by making it smaller

• The perimeter of the new rectangle will be the same as the perimeter of the original rectangle.
• The perimeter of the new rectangle will be 2.5 times as large as the perimeter of the original rectangle.
• The perimeter of the new rectangle will be 5 times as large as the perimeter of the original rectangle.

Suppose the dimensions of a pentagon with an area of 12 are tripled. Describe the changes to the area.

• The area will be 3 times bigger.

• The area will be 9 times bigger.

• The area will be 12 times bigger.

• The area will be 144 times bigger.

If the scale factor is greater than one, the new figure will be

• a reduction
• an enlargement
• a scale
• not proportional

A triangle's 3 sides are increased by a scale factor of 3/4. What is the result on the area of the new figure?

• The area is increased by 3/4.

• The area is increased by 4/3.

• The area is decreased by 9/16.

• Not enough information.

Describe the effect of the change on the perimeter of the given figures. The base and height of a rectangle with base 4 ft and height 5 ft are both doubled.

• The perimeter is doubled.
• The perimeter is quadrupled.
• The perimeter is two more.
• The perimeter is four more.

A rectangle has a base 4 ft and height of 5 feet. If the figure dilated by a scale factor of 2, what will be true about its perimeter?

• The perimeter is doubled.
• The perimeter is quadrupled.
• The perimeter is two more.
• The perimeter is four more.

A rectangle has a base 4 ft and height of 5 feet. If the figure dilated by a scale factor of 2, what will be true about its area?

• The area is doubled.
• The area is multiplied by 4.
• The area stays the same