Monday October 3 rd Wrap up of Chapter 3 -some people need to take Ch 3 test -some need to finish Ch 3 test -others can work on extra credit 3.8 chapter review

Chapter 4 Graphing Linear Equations 4.1 Coordinates and Scatter Plots

Example 1: Plot and label the points: A(2,1), B(5,03), C(-3,0), D(-2,-2), E(0,4), F(-2,3) Label axes Label scale

Example 2: The data below represent the weight and height of a male. At age 13, he was 63 in. tall. Predict his weight at age 13. AgeHeight (in.) Weight (lb)

MondayTuesdayWednesdayThursdayFriday 3 A Ch 3 wrap-up 4 A H D A A H E PSAT-no class 13 A A Quiz New 4.6; End of 1/4 17 A C H A Review 21 D Ch 4 Test Date Assigned-due next dayAssignment 10/4 Tuesday4.1 p #10-26 even, 27-32, /5 Wednesday4.2 p #12-50 even 10/6 Thursday4.2 p215 #52,54,60,62,64,66,67-70 and /7 Friday4.3 p221 #14-40 even, 41-43

How can we graph an equation? 4.2 Graph an equation by using a table of values 4.3 Graphing Using Intercepts 4.6 Graphing Using Slope Intercept Form: y=mx+b

Find the x and y intercepts of 4x+3y=12 Solution: 4x + 3(0) = 12 (substitute 0 for y) 4x = 12 x = 3 The x intercept is 3. The line crosses the x axis at (3,0). 4(0) + 3y = 12 (substitute 0 for x) 3y = 12 y = 4 The y intercept is 4. The line crosses the y axis at (0,4). Use the intercepts to graph the line. By sure to label your axes and mark your scale.

Graph x – 2 =4y Solution: x – 2 = 4(0) (substitute 0 for y) x – 2 = 0 The x intercept is 2. The line crosses the x axis at (2,0). 0 – 2 = 4y (substitute 0 for x) -2 = 4y y = - 1/2 The y intercept is -1/2. The line crosses the y axis at (0,-1/2). Use the intercepts to graph the line. By sure to label your axes and mark your scale.

Graph y = -2x + 25 Solution: 0 = -2x +25 (substitute 0 for y) 2x = 25 x = 12 1/2 The x intercept is 12 1/2 The line crosses the x axis at (12.5,0) y = -2(0) + 25 (substitute 0 for x) y = 25 The y intercept is 25. The line crosses the y axis at (0,25). What is you scale for graphing the line?

Monday October 10 th Bellwork: p224 #1, 5, 11 1.Plot and label the ordered pairs in a coordinate plane: A(-4,1), B(0,2), C(-3,0)

Find three different ordered pairs that are solutions of the equation. Graph the equation. P 224 #5) y=2x-6 XY 02(0)-6=-6 32(3)-6=0 12(1)-6=-4

Find the x and y intercept of the line. Graph the line. Lable the intercepts. 11) y=4-x y=4-0 (insert 0 for x to find y intercept) y=4 y intercept= (0,4) 0=4-x (insert 0 for y to find x intercept) x=4 x intercept = (4,0)

MondayTuesdayWednesdayThursdayFriday 3 A Ch 3 wrap-up 4 A H D A A H E PSAT-no class 13 A A Quiz New 4.6; End of 1/4 17 A C H A Review 21 D Ch 4 Test Date Assigned-due next dayAssignment 10/7 Friday4.3 p221 #14-40 even, /10 Monday4.3 day 2 p221 #44-58 even, all 10/11 Tuesday4.4 p230 16,18,20,24,28,32,36,37,38,42,46,49,52-55, /12 WednesdayNo class because of PSAT 10/13 Thursday4.5 p237 #12-20 even, 21,24,26,28,30,33 10/14 Friday4.6 p244 #14-50 even

4.4 The Slope of a Line

1. Find the slope of the line passing through (-3,0) and (-1,6) Given (x 1,y 1 ) and (x 2,y 2 ), find slope using m = y 2 -y 1 x 2 -x 1

2. Find the slope of the line passing through (-1,-3) and (5,-3) Given (x 1,y 1 ) and (x 2,y 2 ), find slope using m = y 2 -y 1 x 2 -x 1

3. Find the slope of the line passing through (-2,1) and (1,-3) Given (x 1,y 1 ) and (x 2,y 2 ), find slope using m = y 2 -y 1 x 2 -x 1

4. Find the slope of the line passing through (0,-1) and (0,4) Given (x 1,y 1 ) and (x 2,y 2 ), find slope using m = y 2 -y 1 x 2 -x 1

Given (x 1,y 1 ) and (x 2,y 2 ), find slope using m = y 2 -y 1 x 2 -x 1 Key concepts from 4.4

MondayTuesdayWednesdayThursdayFriday 3 A Ch 3 wrap-up 4 A H D A A H E PSAT-no class 13 A A Quiz New 4.6; End of 1/4 17 A C H A Review 21 D Ch 4 Test Date Assigned-due next dayAssignment 10/7 Friday4.3 p221 #14-40 even, /10 Monday4.3 day 2 p221 #44-58 even, all 10/11 Tuesday4.4 p230 16,18,20,24,28,32,36,37,38,42,46,49,52-55, /12 WednesdayNo class because of PSAT 10/13 Thursday4.5 p237 #12-20 even, 21,24,26,28,30,33 10/14 Friday4.6 p244 #14-50 even

Why is slope important?

Goals for today: 4.5 Direct variation Review for Friday quiz Two variables vary directly if k not = 0 and y=kx Think direct variation (y=kx) indirection variation (y=k/x) k=constant of variation, also the slope

Ex.1) Find the constant of variation and the slope for the direct variation model y=-3x y=kx k=constant so k=-3 Ex. 2) The variables x and y vary directly. When x=-3, y=- 30 a)Write an equation that relates x and y y=kx -30=k(-3) k=10 y=10x b) Find the value of y when x=8 y=10x y=10(8) y=80

Ex 3) The incoe at a store varies directly as the advertsing budget. When the owner spent $3000 per month on advertising, the monthly gross income was $120,000. If the owner increases the advertising budget to $5000, how much gross income should they expect? y=kx let x=$advertising and y=$gross 120,000=k(3000) k=40 y=40x If x=$5000, then: y=40(5000) y=$200,000 Or if 3000 = 5000,then 3000y=60,000,000 y=$200, y

MondayTuesdayWednesdayThursdayFriday 3 A Ch 3 wrap-up 4 A H D A A H E PSAT-no class 13 A A Quiz New 4.6; End of 1/4 17 A C H A Review 21 D Ch 4 Test Date Assigned-due next dayAssignment 10/7 Friday4.3 p221 #14-40 even, /10 Monday4.3 day 2 p221 #44-58 even, all 10/11 Tuesday4.4 p230 16,18,20,24,28,32,36,37,38,42,46,49,52-55, /12 WednesdayNo class because of PSAT 10/13 Thursday4.5 p237 #12-20 even, 21,24,26,28,30,33 10/14 Friday4.6 p244 #14-50 even