# slope intercept

Post on 21-Jun-2015

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- 1. Practice converting linear equations into Slope-Intercept Form Its easier than you think

2. Slope intercept form is: y = mx + bOur main goal is to get the y alone on one side of the equation 3. Convert IntoSlope-InterceptForm (divide both sides by 2 to get y alone) (now simplify all fractions) 2 1 4. When an equation is in slope-intercept form: y = mx + b 2 What is the slope?____________ What is the intercept?____________ 1 slope Now look at the equation below Intercept 5. y = 2x + 1 Step 1: Look at they-interceptand plotwhere the graphs cross the y axis. Now look at the graph of the line.Step 2: Use theslope(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. 6. *** Easy *** 5y = 10x + 15 Convert to Slope-Intercept Form: (divide both sides by 5 to get y alone) (now simplify all fractions) y = 2x + 3 7. y = 2x + 3 8. *** Now Try thisConvert 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?____________ 9. *** Check Your Answer *** -3y = -9x - 12 (divide both sides by -3 to get y alone) (now simplify all fractions) y = 3x + 4 Slope =3 Intercept = 4 -3 -3 -3y = -9x - 12 -3 -3-3 10. y = 3x + 4 Slope =3 Intercept = 4 Because there is no room to move up 3 we will have to move down 3 and to the LEFT 1 11. *** medium *** 21x 7y=14 Convert to Slope-Intercept Form: (subtract both sides by 21x) -7y =-21x+ 14 (now divide both sides by -7) y = 3x 2 (simplify all fractions) 12. 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 *** Now Try thisConvert to Slope-Intercept Form *** What is the slope?____________ What is the intercept?____________ 13. 2y + 26 = -6x (subtract both sides by 26) 2y = -6x- 26 (now divide both sides by 2 y = -3x - 13 (simplify all fractions) *** Check Your Answer *** 14. Vocabulary The word intercept means to cross. 15. Vocabulary x-intercept - the point (ordered pair) where a line crosses the x-axis. y-intercept - the point (ordered pair) where a line crosses the y-axis. 16. Intercepts Find the x and y intercepts of the line below. x y -3 -2 -1 1 2 3 3 2 1 -1 -2 -3 17. Intercepts Find the x and y intercepts of the line below. x y Where does the line cross the x-axis? x-intercept is(-2,0) -3 -2 -1 1 2 3 3 2 1 -1 -2 -3 18. Intercepts Find the x and y intercepts of the line below. x Where does the line cross the y-axis? x-intercept is(-2,0) y-intercept is(0,2) Sometimes, this is written asx-intercept = -2and y-intercept = 2. y -3 -2 -1 1 2 3 3 2 1 -1 -2 -3 19. Intercepts Find the x and y intercepts of the line below. x y -3 -2 -1 1 2 3 3 2 1 -1 -2 -3 20. Intercepts Find the x and y intercepts of the line below. x Where does the line cross the x-axis? x-intercept is(1,0) y -3 -2 -1 1 2 3 3 2 1 -1 -2 -3 21. Intercepts Find the x and y intercepts of the line below. x Where does the line cross the y-axis? x-intercept is(1,0) y-intercept is(0,3) y -3 -2 -1 1 2 3 3 2 1 -1 -2 -3 22. Intercepts Find the x and y intercepts of the line below. x y -3 -2 -1 1 2 3 3 2 1 -1 -2 -3 23. Intercepts Find the x and y intercepts of the line below. x Where does the line cross the x-axis? x-intercept is(-1,0) y 3 2 1 -1 -2 -3 -3 -2 -1 1 2 3 24. Intercepts Find the x and y intercepts of the line below. x Where does the line cross the y-axis? x-intercept is(-1,0) y-intercept is(0, ) y -3 -2 -1 1 2 3 3 2 1 -1 -2 -3 25. Intercepts Sometimes, we must find the intercepts without a graph. x y -3 -2 -1 1 2 3 3 2 1 -1 -2 -3 26. Intercepts Sometimes, we must find the intercepts without a graph. We use theequationof the line. 27. Intercepts To find the x intercept, let y = 0 To find the y intercept, let x = 0 Substitute 0 for y. Substitute 0 for x. 28. Intercepts Find the x and y intercepts of the graph of the equation 2x 5y = 10. x-intercept y-intercept The x-intercept is (5,0). The y-intercept is (0,2).