Solving Quadratic Equations

Solving Quadratic Equations

• 1.
  Solving Quadratic Equations
• 2.
  Do Now: Explain the difference(s) between each of the following pairs 4x 2 – 2x and 4x 2 – 2x = 0 x 2 – 16 and x 2 – 16 = 0 x 2 – x – 2 and x 2 – x – 2 = 0 The first in each pair is an expression, the second is an equation . Equations can be solved for a value of the variable, expressions cannot
• 3.
  Explain the difference(s)between each of the following pairs 2x + 4 = 0 and 2x 2 + 4x = 0 x – 16 = 0 and x 2 – 16 = 0 2x – 6 = 8 and x 2 – 4x = 12 The first in each pair is linear (the highest exponent is 1), the second in each pair is quadratic (highest exponent is 2)
• 4.
  How do wesolve quadratic equations? Ex. 1 Solve for x: x 2 – 4x – 12 = 0 (x – 6)(x + 2) = 0 x – 6 = 0 x + 2 = 0 + 6 +6 - 2 -2 x = 6 x = - 2 Steps Set = 0 (if not already = 0) Factor Set each factor = 0 Solve each equation Check each solution in original equation
• 5.
  Practice – Solveeach of the following x 2 – 3x + 2 = 0 x 2 + 2x + 1 = 0 x 2 – 5x – 6 = 0 x 2 + 2x – 8 = 0 x 2 – 4 = 0 x 2 – 3x = 0 Steps Set = 0 (if not already = 0) Factor Set each factor = 0 Solve each equation Check each solution in original equation
• 6.
  Answers x =1,2 or {1,2} x = - 1 or {- 1} x = - 1, 6 or {-1, 6} x = - 4, 2 or {-4,2} x = - 2, 2 or {- 2, 2} X = 0, 3 or {0, 3}