SOLUTION: I am doing quadratic equations, the problem is {{{ X^2-x-12 }}} I understand most of it except for when I get to where the problem says x = -1 sqrt(47)/2 I don't know what to do wi

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Question 366738: I am doing quadratic equations, the problem is I understand most of it except for when I get to where the problem says x = -1 sqrt(47)/2 I don't know what to do with the square root symbol. I know how to find the vertex but I don't have the roots to graph the parabola, If some one could help me with this I would be grateful.
Found 2 solutions by Alan3354, jim_thompson5910:
You can put this solution on YOUR website!
You didn't show an equation. All equations have an equal sign.
If you mean you missed a sign somewhere, it's sqrt(49).
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 Solved by pluggable solver: SOLVE quadratic equation (work shown, graph etc) Quadratic equation (in our case ) has the following solutons: For these solutions to exist, the discriminant should not be a negative number. First, we need to compute the discriminant : . Discriminant d=49 is greater than zero. That means that there are two solutions: . Quadratic expression can be factored: Again, the answer is: 4, -3. Here's your graph:

You can put this solution on YOUR website!

Notice that the quadratic is in the form of where , , and

Let's use the quadratic formula to solve for "x":

Plug in , , and

Negate to get .

Square to get .

Multiply to get

Rewrite as

Multiply and to get .

Take the square root of to get .

or Break up the expression.

or Combine like terms.

or Simplify.

So the solutions are or

So the roots (or x-intercepts) are (4,0) and (-3,0)