Chapter 8 Integers, Number Lines, and Coordinate Plane

• Quadrant I

• Quadrant II

• Quadrant III

• Quadrant IV

Evelyn withdraws $20 from her bank account.

What integer can be used to represent the situation? Explain.

• -20 because she took $20 out of her bank account.

• +20 because she added $20 to her bank account.

Graph -2 and its opposite on the number line.

a

b

2

-2

Plot the points that represent the locations of the swings and the slide.

a

b

T

S

If each unit on the coordinate plane represents 10 feet, how far are the swings from the slide?

Which point lies on the x-axis?

• (0, 4)

• (-3, 0)

• (1, 1)

• (-1, 1)

Margaret and Sheng are mountain climbing. They started at sea level and descended down a cliff. Margaret's location can be represented by -32 meters. Sheng's location can be represented by -35 meters. Who is closer to the starting point? Explain.

• Margaret, because the absolute value of -32 is a distance closer to zero

• Sheng, because the absolute value of -35 is a distance closer to zero.

Polygon ABCD has vertices A(-1, 3.5), B(4, 3.5), C(4,1), and D(-1,1). Is polygon ABCD a rectangle? Explain

• Yes, because point A and D have the same x values and points B and C have the same x values.

• Yes, because points A and B have the same y values and points C and D have the same y values.

• Yes, because only two x values and two y values are used in all 4 points, so it makes 4 straight lines.