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anonymous
 5 years ago
THIS is the last quadratic equation I need help with tonight, promise
anonymous
 5 years ago
THIS is the last quadratic equation I need help with tonight, promise

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anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0\[y ^{2}+3y3=0\] is the equation....and so far I have \[3 + and \sqrt{21}\over 2\]

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.07 times 3 is 21.. so maybe i wasn't sure if they could simplify

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Nope. the square root of 21 is not a nice number.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0ok, so what I have is correct. And they are 2 real solutions?

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0is the thing under the square root a negative number?

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0no, so if it was y squared it would be non real?

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Yes it would be nonreal if a was negative in this case.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0or if c was positive and a was positive it would be nonreal

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0You know what we are finding with this equation right?

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Imagine we had some equation like: f(y) = y^2 + 3y 3

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0And we graphed it. What would it look like?

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Where our horizontal axis is y, and the vertical axis is f(y)

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0http://www.wolframalpha.com/input/?i=graph+f+%3D+y^2+%2B+3y++3

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0When we say the expression equals 0, we are finding where this parabola crosses the horizontal axis.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0What is the values for y that make this curve touch the line f(y) = 0

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0So when we don't get a real solution it means that that curve never touches the f(y)=0 line. Like this would be the graph if it was y^2 instead. http://www.wolframalpha.com/input/?i=graph+f+%3D+y^2+%2B+3y++3 And you can see that since it's opening downward it never crosses the 0 horizontal line.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0And this would be the graph if a and c were both positive: http://www.wolframalpha.com/input/?i=graph+f+%3D+y^2+%2B+3y+%2B+3 Again, no real solutions because the graph doesn't cross f(y)=0.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0I hope that helps a bit to put into context what we're doing.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Sorry i was away from this site for a bit. I will check that out, looks helpful! THanks again!
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