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Algebra 1

9.6.5 Practice

Algebra 19.6.5 Practice
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Complete the following questions to practice the skills you have learned in this lesson.

For each equation in questions 1 – 5, identify the values of a , b , and c that you would substitute into the quadratic formula to solve the equation.

  1. 3 x 2 + 8 x + 4 = 0
  1. What is the value of a ?
  1. What is the value of b ?
  1. What is the value of c ?
  1. 2 x 2 − 5 x + 2 = 0
  1. What is the value of a ?
  1. What is the value of b ?
  1. What is the value of c ?
  1. − 9 x 2 + 13 x − 1 = 0
  1. What is the value of a ?
  1. What is the value of b ?
  1. What is the value of c ?
  1. x 2 + x − 11 = 0
  1. What is the value of a ?
  1. What is the value of b ?
  1. What is the value of c ?
  1. − x 2 + 16 x + 64 = 0
  1. What is the value of a ?
  1. What is the value of b ?
  1. What is the value of c ?
  1. For each equation, use the quadratic formula to solve the equation, then choose the correct two solutions for x . 
  1. x 2 + 9 x + 20 = 0
  1. 4
  2. -4
  3. -5
  4. 5
  5. 1
  6. 9
  7. 20
  1. x 2 − 10 x + 21 = 0
  1. 3
  2. -7
  3. 21
  4. -10
  5. 1
  6. -4
  7. 7
  1. 3 x 2 − 5 x + 1 = 0
  1. 13 6 + 5 6
  2. -1
  3. 5 6 − 13 6
  4. 13 6 − 5 6
  5. − 18 6 − 3
  6. 5 6 + 13 6
  7. 18 6 − 3

For each equation for questions 7 – 12, identify the values of a , b , and c that you would substitute into the quadratic formula to solve the equation.

  1. x 2 + 9 x + 18 = 0
  1. What is the value of a ?
  1. What is the value of b ?
  1. What is the value of c ?
  1. 4 x 2 − 3 x + 11 = 0
  1. What is the value of a ?
  1. What is the value of b ?
  1. What is the value of c ?
  1. 81 − x + 5 x 2 = 0
  1. What is the value of a ?
  1. What is the value of b ?
  1. What is the value of c ?
  1. 45 x 2 + 3 x = 1 3
  1. What is the value of a ?
  1. What is the value of b ?
  1. What is the value of c ?
  1. 0
  2. 1
  3. 1 3
  4. − 1 3
  1. 121 = x 2
  1. What is the value of a ?
  1. What is the value of b ?
  1. What is the value of c ?
  1. 7 x + 14 x 2 = 42
  1. What is the value of a ?
  1. What is the value of b ?
  1. What is the value of c ?
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