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What is the equation of the line in slope-intercept form?. m =. b =. -2. What is the equation of the line in slope-intercept form?. m =. 3. b =. Graph the equation…. First calculate the slope and y-int. m =. -4. b =. Plot the y-intercept. m =. -4. b =.
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What is the equation of the line in slope-intercept form? m = b = -2
What is the equation of the line in slope-intercept form? m = 3 b =
Graph the equation…. First calculate the slope and y-int. m = -4 b =
Plot the y-intercept. m = -4 b =
Apply slope from y-intercept. m = -4 b =
Draw line through two points. m = -4 b =
Graph each equation: m = 1 b =
True or False. The y-intercept of the line is -4. It's 4, not -4.
Write an equation from a graph EXAMPLE 2 for Example 1 GUIDED PRACTICE Graph the line that passes through the points. Find the slope. 1. (5, 2) and (4, –1)
EXAMPLE 2 Graph the line that passes through the points. Find the slope. (3, 5) and (6, –1).
EXAMPLE 3 Graph the line that passes through the points. Find the slope. (– 2, 4) and (4, 4).
EXAMPLE 4 Graph the line that passes through the points. Find the slope. (3, 5)and(3, 1).
Write an equation from a graph for Examples 2, 3 and 4 GUIDED PRACTICE Graph the line that passes through the points. Find the slope. (0, 6) and (5, –4)
INTERNET CAFE The table shows the cost of using a computer at an Internet cafe for a given amount of time. Find the rate of change in cost with respect to time. EXAMPLE 5 Find a rate of change
change in cost = change in time 3.5 = 14–7 = 4– 2 7 = 2 ANSWER The cost to use the Internet café is is $3.50 for one hour. EXAMPLE 5 Find a rate of change SOLUTION Rate of change
Convert Into Slope-Intercept Form (divide both sides by 2 to get y alone) (now simplify all fractions) 2 1
Intercept slope Now look at the equation below…… When an equation is in slope-intercept form: y = mx + b 2 What is the slope? ____________ 1 What is the intercept? ____________
Now look at the graph of the line. y = 2x + 1 Step 1: Look at the y-intercept and plot where the graphs cross the “y” axis. Step 2: Use the slope (rise/run) to determine the next point and plot. Step 3: Draw a line through both points. Be sure to extend pass point and put arrow at both ends.
*** Easy *** Convert to Slope-Intercept Form: 5y = 10x + 15 (divide both sides by 5 to get y alone) (now simplify all fractions) y = 2x + 3 BRAVO!!
*** Now Try this Convert to Slope-Intercept Form*** -3y = -9x - 12 Step 1: divide both sides by -3 to get y alone Step 2: Simplify all fractions Step 3: Write your equation in y = mx + b What is the slope? ____________ What is the intercept? ____________
-3-3 -3y = -9x - 12 -3-3 -3 *** Check Your Answer *** -3y = -9x - 12 (divide both sides by -3 to get y alone) (now simplify all fractions) y = 3x + 4 Wow, you’re good at this!! Slope = 3 Intercept = 4
*** medium *** Convert to Slope-Intercept Form: 21x – 7y =14 (subtract both sides by 21x) (now divide both sides by -7) -7y = -21x + 14 (simplify all fractions) y = 3x – 2
*** Now Try this Convert to Slope-Intercept Form*** 2y + 26 = -6x Step 1: Subtract both sides by 26 Step 2: Divide both sides by 2 to get y by itself Step 3: Simplify all fractions What is the slope? ____________ What is the intercept? ____________
*** Check Your Answer*** 2y + 26 = -6x (subtract both sides by 26) (now divide both sides by 2 2y = -6x - 26 (simplify all fractions) y = -3x - 13 You are a math wizard!