Lesson 8: Practice Problems

Problem 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 $B$ .

6 cm by 1.5 cm
10 cm by 2 cm
13 cm by 4 cm
18 cm by 4.5 cm
80 cm by 20 cm

Problem 2

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 $B$ ? If so, what is the scale factor?
Is Rectangle $B$ a scaled copy of Rectangle $A$ ? If so, what is the scale factor?
Explain how you know that Rectangle $C$ is not a scaled copy of Rectangle $B$ .
Is Rectangle $A$ a scaled copy of Rectangle $C$ ? If so, what is the scale factor?

Problem 3

Here are three polygons.

Draw a scaled copy of Polygon $A$ with scale factor $\frac{1}{2}$ .
Draw a scaled copy of Polygon $B$ with scale factor 2.
Draw a scaled copy of Polygon $C$ with scale factor $\frac{1}{4}$ .

Problem 4 From Unit 1 Lesson 12

In the picture lines $A B$ and $C D$ are parallel. Find the measures of the following angles. Explain your reasoning.

Two parallel line with transversal, F intersecting them at points B and C. One line has points D and E and second line has point A. Point B is 38 degrees.

$∠ B C D$
$∠ E C F$
$∠ D C F$

Problem 5 From Unit 1 Lesson 13

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

$40^{\circ}$ , $50^{\circ}$ , $60^{\circ}$
$50^{\circ}$ , $60^{\circ}$ , $70^{\circ}$
$60^{\circ}$ , $70^{\circ}$ , $80^{\circ}$
$70^{\circ}$ , $80^{\circ}$ , $90^{\circ}$

Problem 6

Quadrilateral $A$ has side lengths 3, 6, 6, and 9. Quadrilateral $B$ is a scaled copy of $A$ with a shortest side length equal to 2. Jada says, “Since the side lengths go down by 1 in this scaling, the perimeter goes down by 4 in total.” Do you agree with Jada? Explain your reasoning.