linear equations
Transcription
linear equations
Algebra Final Exam Solving Linear Equations Topical Review Procedures Solve for x: 4x + 3 = 11 4x + 3 = 11 -3 -3 4x = 8 4 4 x=2 Box VARIABLE TERM and Solve for variable Get BOXED TERM by itself on one side of the = sign Solve for VARIABLE BOXED TERM: Equations with Fractions *6 *6 *6 5 x 17 102 6 Type 1: Fraction with no ( ) in problem Multiply EVERY term by the bottom # to get rid of the fraction 5x 102 612 +102 +102 5x = 714 5 5 x = 142.8 This will cancel the Fraction out Then solve basic equation *4 *4 3 (3x 8) 15 4 Type 2: Fractions with ( ) in problem Multiply both sides by bottom # to get rid of the fraction This will cancel the Fraction out 3(3x 8) 60 Distribute remaining # in front of ( ) Then solve basic equation 9x 24 60 -24 -24 9x = 36 9 9 x=4 SOLVING INEQUALITY EQUATIONS Solve the inequality equation using procedures from above Graph the solution on a number line using correct endpoints (open or closed) < or > have open circles –2(x – 3) > 5(x – 9) 2x 6 5x 45 -6 -6 -2x > 5x – 51 -5x -5x -5x -7x > -51 -7 -7 51 x 7 or have closed circles Shade -Pick a test point to determine truth value. Shade where value is TRUE Write answer using Interval Notation ( ) or [ ] Solution Set < or > and or 51 7 0 51 7 (, REMEMBER: When you DIVIVDE by a NEGATIVE number you MUST FLIP the inequality sign 51 ] 7 Solve the following: 3 (3x 8) 15 4 1. 8y – (5y + 2) = 16 2. 3. 9x – 6 = 5x – 15 + x 4. 3x 7x 7 3(2x 1) 2 6. 3x 2 8. x3 4 (x 1) 2 5 5 5 x 8 8 5. 2x 7. 1 7 5x (3x 8) 4 x 2 2 9. Solve and graph the inequality: 2 x 1 15 3 1 x 2 3 10. Solve and graph the inequality: 4(2 – x) -2x 11. What is the value of x in the equation x2 1 5 3 6 6 (1) 4 (2) 6 12. 13. (3) 8 (4) 11 Which value of x satisfies the equation: (1) 8.25 (3) 19.25 (2) 8.89 (4) 44.92 The inequality 7 (1) x > 9 (2) x 14. ? 3 5 7 9 x 20 ? 3 28 2 x x 8 is equivalent to 3 (3) x < 9 3 (4) x 5 Which of the following represents an expression? (1) x 7 4 (3) 3x 2 5 (2) 5X 8 12 (4) 2 X 2 30 15. Given the equation ax + b = c, then x can be expressed as cb c (1) x (3) x b a a bc c b (2) x (4) x a a 16. The length of a rectangle is 15 and its width is w. The perimeter of the rectangle is, at most, 50. Which of the inequalities could be used to find the longest possible width? (1) 15 w 50 (2) 30 2w 50 (3) 30 2w 50 (4) 15 w 50 17. 18. Given 2x + ax – 7 > -12, determine the largest integer value of a when x = -1. Solve the inequality below to determine and state the smallest possible value for x in the solution set. Write your answer in interval notation. 3(x + 3) ≤ 5x – 3 19. At the Smith’s wedding, the bride and groom paid $11,374 for their guests to eat and rent the ballroom for dancing after dinner. The venue charges $79 per adult, and $45 per child. If there were 122 more adults than children, write an equation to represent this situation. You do not have to solve. 20. Val and Max work at a dance store. Val is paid $210 per week plus 5% of his total sales in x dollars, which is represented by V(x) 210 0.05x . Max is paid $360 per week plus 1% of his total sales in x dollars, which is represented by M(x) 360 0.01x . Determine the value of x dollars that will make their weekly pay the same.