Practice converting linear equations into Slope-Intercept Form It’s easier than you think…
y = mx + b Slope intercept form is: Our main goal is to get the y alone on one side of the equation
Convert Into Slope-Intercept Form (divide both sides by 2 to get y alone) (now simplify all fractions) 2 1
When an equation is in slope-intercept form: y = mx + b slope Intercept Now look at the equation below…… 2 What is the slope? ____________ 1 What is the intercept? ____________
y = 2x + 1 Now look at the graph of the line. 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 *** 5y = 10x + 15 y = 2x + 3 BRAVO!! 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? ____________
*** Check Your Answer *** -3y = -9x - 12 (divide both sides by -3 to get y alone) -3 -3 (now simplify all fractions) -3y = -9x - 12 -3 -3 -3 y = 3x + 4 Wow, you’re good at this!! Slope = 3 Intercept = 4
*** medium *** 21x – 7y =14 -7y = -21x + 14 y = 3x – 2 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!
Find the Equation of the Line What is the y-intercept? b = -2 What is m? m = Up 3 and over 2 y = x -2 x y
Find the Equation of the Line b = ? b = 4 m = ? m = 0 y = 0x+4 y=4 x y
Find the Equation Given the Slope and y-intercept 1) m = -3, b = 1 y = -3x + 1 2) m = - , b = -4 y = - x - 4
Find the Equation Given the Slope and a Point Given m = -1, (2, 1) 2=x, 1=y First, calculate b by substituting the slope and the coordinates into y = mx + b. y = -1x + b 1 = -1(2) + b 1 = -2 + b 3 = b y = -1x + 3
Find the Equation Given the Slope and a Point Given m = -4, (-3,5) Remember to substitute (-3=x, 5=y) First, calculate b by substituting the slope and the coordinates into y = mx + b.
Find the Equation Given Two Points Given (-1, 3) and (2, 1) First, calculate the slope: (difference in y’s) (difference in x’s) Second, find b. Use either point... m = , (2, 1) 1 = (2) + b 1 = + b = b
Find the Equation Given Two Points Write in slope-intercept form the equation of the line that passes through the point (3, -2) and (6,0). Step 1: Find the slope Step 2: Substitute slope and one point into y=mx + b
Write the equation of the line in the graph in slope-intercept form.
Write the equation of the line in the graph in slope-intercept form.