Open Up - Grade 8 - Mathematics - Unit 2 - Lesson 1

Rectangle A measures 12 cm by 3 cm. Rectangle B is a scaled copy of Rectangle A.

Select all of the measurement pairs that could be the dimensions of Rectangle B.

Rectangle A has length 12 and width 8. Rectangle B has length 15 and width 10. Rectangle C has length 30 and width 15.

Is Rectangle A a scaled copy of Rectangle B?

Rectangle A has length 12 and width 8. Rectangle B has length 15 and width 10. Rectangle C has length 30 and width 15.

Is Rectangle B a scaled copy of Rectangle A?

Rectangle A has length 12 and width 8. Rectangle B has length 15 and width 10. Rectangle C has length 30 and width 15.

Explain how you know that Rectangle C is not a scaled copy of Rectangle B.

Rectangle A has length 12 and width 8. Rectangle B has length 15 and width 10. Rectangle C has length 30 and width 15.

Is Rectangle A a scaled copy of Rectangle C?

Here are three polygons.

Draw a scaled copy of Polygon A with scale factor \frac{1}{2} .

Draw a scaled copy of Polygon A with scale factor 2.

Draw a scaled copy of Polygon A with scale factor \frac{1}{4}.

Which of these sets of angle measures could be the three angles in a triangle?

In the picture lines AB and CD are parallel. Find the measures of the following angles.

(Only one measurement per angle)