SOLUTION: factor by completing the square. please show how the work is done. I can get the answer but do not know how to work the problem. Thank you.
x^2+3x-1=0
Question 652418: factor by completing the square. please show how the work is done. I can get the answer but do not know how to work the problem. Thank you.
x^2+3x-1=0 Answer by ankor@dixie-net.com(22740) (Show Source):
You can put this solution on YOUR website! x^2 + 3x - 1 = 0
add 1 to each side
x^2 + 3x + ___ = 1
Fill in the blank with a value that will complete the square
To find this value, divide the coefficient of x by 2 and square it = 2.25, therefore we add 2.25 to both sides
x^2 + 3x + 2.25 = 1 + 2.25
x^2 + 3x + 2.25 = 3.25
:
This square factors to
(x + 1.5)^2 = 3.25
:
Find the square root of both sides
x + 1.5 = +/-
:
Subtract 1.5 from both sides, two solutions
x = -1.5 +
and
x = -1.5 -
