Question 51308This question is from textbook
: I am using the quadratic formula on 3x^2 = 11x + 4; 3x^2 - 11x + 4 = 0; 3x^2 - 11x - 4 = -2; I have to convert the 5.5 to a fraction, but I am confused. The answer is 1/3,-4 or the other way around (I think). I need an assist please.
This question is from textbook
Answer by rapaljer(4671) (Show Source):
You can put this solution on YOUR website! I'm confused too!! You have three different quadratic equations, and I don't see how any of them relate to changing 5.5 to a fraction.
However, the first equation is
, which becomes
, which factors into

or 
or .
This works very well by factoring, so you don't need the quadratic formula, unless you specifically wanted to do it by quadratic formula. In this case, algebra.com has a "pluggable solver" that looks like this:
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=169 is greater than zero. That means that there are two solutions: .


Quadratic expression can be factored:

Again, the answer is: 4, -0.333333333333333.
Here's your graph:
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R^2 at SCC
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