Do Now 10/26/09 Take out HW from Friday. Take out HW from Friday. –Text p. 219, #6 & 8, even, 38 Copy HW in your planner. Copy HW in your planner. –Text p. 229, #8-22 even #28-40 even, 46 –Quiz Sections 4.1 – 4.3 Wednesday In your notebook, define the word INTERCEPT in your own words. Use the word in a sentence that is NOT math related. In your notebook, define the word INTERCEPT in your own words. Use the word in a sentence that is NOT math related.

Homework Text p. 219, #6 & 8, even, 38 6) not a solution 8) not a solution 16-22) graphs on overhead 24) A 26) y ≥ -2 28) y = 4 30) -5 ≤ y ≤ 3 32) The equations are the same, each term in the first equation was multiplied by 2 to get the second equation. 3x – 3y = 9. 38) a. $190; substitute 3 in for f and solve. b. 13 1/3 yd; substitute 500 in for C and solve. b. 13 1/3 yd; substitute 500 in for C and solve.

Linear Function- The equation Ax + By = C represents a linear function as long as B = 0.

Graph a Function SOLUTION STEP 1 Make a table. STEP 2 STEP 3 Connect the points with a ray because the domain is restricted. Plot the points. STEP 4 Identify the range. From the graph, you can see that all points have a y-coordinate of 1 or more, so the range of the function is y ≥ 1. Graph the function y = – 3x + 1 with domain x ≤ 0. Then identify the range of the function. Graph the function y = – 3x + 1 with domain x ≤ 0. Then identify the range of the function. x 0 – 1 – 2 – 3 – 4 y

Objective SWBAT graph a linear equation using intercepts

Section 4.3 “Graph Using Intercepts” Section 4.3 “Graph Using Intercepts” x-intercept- the x-coordinate of the point where the graph crosses the x-axis To find the x-intercept, solve for ‘x’ when ‘y = 0.’ Find the x-intercept of the graph x + 7y = 28. 2x + 7y = 28 2x + 7(0)= 28 2x = 28 x = 14 x = 14

y-intercept- the y-coordinate of the point where the graph crosses the y-axis Section 4.3 “Graph Using Intercepts” Section 4.3 “Graph Using Intercepts” To find the y-intercept, solve for ‘y’ when ‘x = 0.’ Find the y-intercept of the graph 2x + 7y = 28. 2x + 7y = 28 2(0)+ 7y= 28 7y = 28 y = 4 y = 4

Use Intercepts to Graph an Equation Graph the equation x + 2y = 4. x + 2y = 4 x =  x- intercept 4 Find the x-intercept x + 2(0) = y = 4 y =  y- intercept 2 x + 2y = 4 Find the y-intercept Plot points. The x- intercept is 4, so plot the point (4, 0). The y- intercept is 2, so plot the point (0, 2). Draw a line through the points.

Use Intercepts to Graph an Equation Graph the equation 6x + 7y = 42. 6x + 7y = 42 x =  x- intercept 7 Find the x-intercept 6x + 7(0)= 42 6(0) + 7y = 42 y =  y- intercept 6 6x + 7y = 42 Find the y-intercept Plot points. The x-intercept is 7, so plot the point (7, 0). The y- intercept is 6, so plot the point (0, 6). Draw a line through the points.

Use a Graph to Find Intercepts The graph crosses the x-axis at (2, 0). The x-intercept is 2. The graph crosses the y-axis at (0, – 1). The y-intercept is – 1.

The graph crosses the x-axis at (–4, 0). The x-intercept is –4. The graph crosses the y-axis at (0, 2). The y-intercept is 2.

Problem Solving Using Linear Equations You are working at a local park and are in charge of renting skateboards and bikes. You rent bikes for $8.00 a day and skateboards for $4.00 a day. At the end of the day you have made a profit of $1200. skateboards bikes 4x + 8y = 1200 Write an algebraic equation to represent the situation. Use ‘x’ for skateboards and ‘y’ for bikes Using the graph, make a table of values to show the different combinations of rentals that could have resulted in a $1200 profit.

Homework Text p. 229, #8-22 even #28-40 even, 46 Text p. 229, #8-22 even #28-40 even, 46 24