1. MATHPOWER TM 10, WESTERN EDITION Chapter 6 Coordinate Geometry 6.4 6.4.1

2. The slope of a line describes a constant or average rate of change. The rate can be found by dividing the change in the y-quantity by the change in the x-quantity. Jake cycled 7.5 km in 25 min and 22.5 km in 75 min. Rhonda cycled 8.75 km in 35 min and 16.25 km in 65 min. A) Calculate Jake’s rate of cycling. B) Calculate Rhonda’s rate of cycling. = 18 km/h = 15 km/h Jake Rhonda (35, 8.75) (65, 16.25) (25, 7.5) (75, 22.5) 6.4.2 Slope as Rate of Change

3. One year, Lillian paid $4250 in taxes on a taxable income of $25 000. In the previous year, she paid $3740 in taxes on a taxable income of $22 000. A) Determine the rate of income tax, as a percentage of taxable income. B) Describe the rate of income tax in words. For every $100 in taxable income, $17 is paid in taxes. C) If Lillian had a taxable income of $26 500, how much income tax would she expect to pay? 26 500 x 0.17 = 4505She would expect to pay $4505. D) If she paid $3612.50 in income tax, what is her income? 17% of n = $3612.50 n = 3612.50 ÷ 0.17 n = 21 250 Her income is $21 250. The income tax rate is 17%. 6.4.3 Applications and Problem Solving = 0.17

4. Pages 271 and 272 1, 2, 3, 5 6.4.4 Suggested Questions: