How do you solve 3x^2 - 10 = 2x3x2−10=2x by completing the square?

1 Answer
EZ as pi
May 10, 2016
  1. Move the constant to the right
  2. Make a = 1
  3. Add on (b/2)^2(b2)2 to both sides
  4. Write as (x +- b/2)^2 =
  5. Find square toot of both sides
  6. Solve twice - pos and neg square root

3x^2 - 10 = 2x rArr 3x^2 - 2x = 103x2−10=2x⇒3x2−2x=10

x^2 - (2x)/3 + color(red)((1/3)^2) = 10/3 + color(red)((1/3)^2)x2−2x3+(13)2=103+(13)2
(x - 1/3)^2 = 31/9(x−13)2=319

x - 1/3 = +-sqrt31/3x−13=±√313

x = sqrt31/3 + 1/3 " or " x = -sqrt31/3 + 1/3x=√313+13 or x=−√313+13

x = 2.189 or x = -1.523x=2.189orx=−1.523

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