SOLUTION: Could someone please show me how to solve by completing the square? x^2+3/2 x=3

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Question 528491: Could someone please show me how to solve by completing the square? x^2+3/2 x=3
Answer by Edwin McCravy(20054) About Me  (Show Source):
You can put this solution on YOUR website!
x² + 3%2F2x = 3

Multiply the coefficient of x, which is 3%2F2 by 1%2F2, getting 3%2F4.
Now square 3%2F4, getting %283%2F4%29%5E2 = 9%2F16

Add +9%2F16 to both sides of the equation:

x² + 3%2F2x + 9%2F16 = 3 + 9%2F16

The left side will now factor as (x + 3%2F4)(x + 3%2F4) or (x + 3%2F4)².  So we have:

(x + 3%2F4)² = 3 + 9%2F16

We will combine the terms on the right by getting the LCD of 16.
Then 3 + 9%2F16 becomes 48%2F16 + 9%2F16 or 57%2F16.
So we now have:

(x + 3%2F4)² = 57%2F16

Next we use the principle of square roots:

x + 3%2F4 = ±sqrt%2857%2F16%29

x + 3%2F4 = ±sqrt%2857%29%2F4%29

Solve for x by adding -3%2F4 to both sides:

      x = -3%2F4 ± sqrt%2857%29%2F4%29

or you can write it:

      x = %28-3+%2B-+sqrt%2857%29%29%2F4

Edwin