Question 153536: Please help me solve the following problem:
Solve: x^2 + 3x - 4 = 0
Found 2 solutions by stanbon, josmiceli:
Answer by stanbon(75887)   (Show Source):
Answer by josmiceli(19441)  (Show Source):
You can put this solution on YOUR website! 
Solving this means finding the roots, or finding
the values of  that make 
true.
If I just say, off the top of my head,  for
a solution, then I'm saying  and
That's not true, so is not a solution
One way to solve this is by completing the square.
First add  to both sides
Now take one-half of the coefficient of the term,
square it, and add it to both sides, like this:
This is the same as
Now take the square root of both sides
and also
 (since  has a + and a - square root)
Subtract  from both sides
And also
So, the solutions are and
Plug these values into the equation to see if they
are roots, for instance:
So, is a solution
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