Linear Equations Reveiw 1 SUMMARY OF ALGEBRA CONCEPTS – EQUATIONS & FORMULAS y mx b Slope Intercept Form STRENGTHS: (Graphing, Finding slope, Finding y intercept) (m is the slope and b is the y-Intercept) y y1 m( x x1 ) Point Slope Form STRENGTHS: (Easy to create equation) (m is the slope and ( x1 , y1 ) is a point) Ax By C Standard Form STRENGTHS: (Find x & y intercepts, System of Equations) (The A coefficient must be positive and No Fractions for any values of A, B and C.) SYSTEM OF EQUATION Method #1 – Graphing 2x + y = 5 y = -4x + 7 Method #2 – Substitution 2x + y = 5 y = -4x + 7 2x + (-4x + 7) = 5 -2x + 7 = 5 -2x =--2 x=1 6 4 2 y = -4(1) + 7 = 3 Method #3 - Elimination 2x + y = 5 y = -4x + 7 2x + 1y = 5 4x + 1y = 7 (subtract) -2x + 0y = -2 x=1 y = -4(1) + 7 = 3 5 Answer (1,3) Answer (1,3) Answer (1,3) KEY FORMULAS DISTANCE FORMULA x2 x1 y2 y1 2 SLOPE FORMULA y2 y1 m x2 x1 MIDPOINT FORMULA 2 x1 x2 y1 y2 , 2 2 xm , ym PYTHAGOREAN THEOREM a 2 b2 c2 QUADRATIC EQUATION 2 0 ax bx c b b2 4ac x 2a Linear Equations Reveiw 2 1. Given points A (-2,4) and B (4,8), which of the following represents the slope of AB ? A. 2 B. 2 3 C. 2 3 D. 3 2 2. Given points A (3,-3) and B (2,-5), which of the following represents the slope of AB ? A. 2 B.-8 C.-2 D.8 3. Given points A (-7,3) and B (-1,1), which of the following represents the slope of AB ? A. 3 B. -3 C. 1 3 D. 1 3 4.The line 3x – 4y = 12 has a: A. Positive Slope B. Negative Slope C. Zero Slope D. Undefined Slope B. Negative Slope C. Zero Slope D. Undefined Slope B. Negative Slope C. Zero Slope D. Undefined Slope B. Negative Slope C. Zero Slope D. Undefined Slope B. Negative Slope C. Zero Slope D. Undefined Slope 5.The line x = 7 has a: A. Positive Slope 6.The line -4y = 8x + 40 has a: A. Positive Slope 7.The line y = -5 has a: A. Positive Slope 8.The line 5x + 7y = -14 has a: A. Positive Slope 9. The equation of the line that has a slope of 5 and goes through (1,-2) is: A. y = 5x + 1 B. y = 5x - 7 C. y = 5x + 3 D. y = 5x – 2 10. The equation of the line that has a slope of -1 and goes through (-3,0) is: A. y = -1x B. y = -1x - 3 C. y = -1x + 3 D. y = 1x – 3 12. Which of the following equations has a slope of 2 and a y intercept of -3 A. y = -2x - 3 B. 2x – y + 3 = 0 C. 6 = 4x – 2y D. y – 2x = 3 13. How solutions would occur when you graph, y = 2x – 1 and 4x – 2y = 12? A. None B. One C. Two D. Infinite Linear Equations Reveiw 3 14. How solutions would occur when you graph, y = 2x – 1 and x + 2y = 4? A. None B. One C. Two D. Infinite 15. How solutions would occur when you graph, y = x – 1 and x + y – 2 = 0? A. None B. One C. Two D. Infinite Determine whether the following are (T)rue or (F)alse. If False tell why! 16. A positive slope rises to the right. T or F 17. A negative slope falls to the left. T or F 18. Slope is the rise over the run. T or F 19. y = 3x – 8 has a positive slope T or F 20. y – 6 = 5(x – 9) has a negative slope. T or F 21. 3x + 4y = 12 has a negative slope. T or F 22. -4y = 8x – 3 has a negative slope. T or F 23. The slope of x = -3 is zero. T or F 24. If A (-3,5) and B (-5,7), then the slope of AB is -1. T or F 25. If A (2,3) and B (4,9), then the slope of AB is 3. T or F 26. If A (-1,4) and B (5,5), then the slope of AB is 1 . 6 T or F 27. The equation of a vertical line through point A (-4,8) is x = -4. T or F 28. The equation of a vertical line through point A (-2,-5) is x = -5. T or F 29. The equation of a horizontal line through point A (–1,3) is y = 3. T or F 30. The equation of a horizontal line through point A (3,9) is y = -9. T or F 31. Write the equation of a line in slope intercept form. a) m = 2 (3,5) b) m = -4 (4,0) c) m = 3 5 (5,6) Linear Equations Reveiw 4 32. Write the equation of a line in slope intercept form. a) b) _____________________ _____________________ 33. Write the equation of a line in point slope form. 2 b) m = (6,3) a) m = 2 (-3,-1) 3 ________________________ ________________________ 34. Determine the x and y intercepts of the line. a) 2x – 5y = 20 b) y = 1x - 3 ( ____ , 0) (0, _____) ( ____ , 0) 35. Graph the following lines a) y = 2x + 1 and y – 1 = -3 (x – 3) b) y = c) ________________________ c) m = -5 (-7,3) ________________________ c) 3x - 2y = 18 (0, _____) 2 3 x -5 and y = x+7 3 2 ( ____ , 0) (0, _____) c) 2x - 3y = 6 and 3x + 2y = 18 Linear Equations Reveiw 5 36. Determine if the following systems of linear equations have (O)ne Solution, (N)o Solutiion or (I)nfinite Solutions. a) b) c) y 3x 8 2 y x 2 y 3x 5 3y x 2 1 3x y 2 y x4 2 O or N or I O or N or I O or N or I 37. Solve the system of equations. a) y 7 x 11 b) 1x 2 y 1 y 5x 5 2 x 3 y 3 c) d) 1 x5 2 3 y x5 4 y 5 x 4 y 8 2 x 4 y 20 Linear Equations Reveiw 6 38. a) Determine the coordinate(s) of any points of intersection between the circle ( x 1) 2 y 1 25 2 and the line, y = 2x - 2. b) After determining the points of intersection, now graph the circle and the line to confirm your calculations.