You can
put this solution on YOUR website!I need help with this problem
32. 3x² - x - 2 = 0 solve for x by completing the square
solve for x by completing the square
3x²-x=2 x²-x/3+2/9= 2/3+2/9 (x-2/3)2= 6/9
x-2/3+6/9 x = 2/3 This is were I get confused.
That's wrong! The 2/9 in the second step should be 1/36.
The rule is:
1. Multiply the coefficient of x by 1/2.
-x/3 means (-1/3)x, so the coefficient of x is -1/3
We multiply that 1/2
(-1/3)(1/2) = -1/6
2. Square the result.
So we square -1/6 and get +1/36
3. Add that to both sides
x2 - x/3 + 1/36 = 2/3 + 1/36
(x - 1/6)² = 24/36 + 1/36
(x - 1/6)² = 25/36
Take square roots of both sides
x - 1/6 = ±5/6
x = 1/6 ± 5/6
Using the + sign:
x = 1/6 + 5/6
x = 6/6
x = 1
Using the - sign:
x = 1/6 - 5/6
x = -4/6
x = -2/3
Edwin
AnlytcPhil@aol.com