Need help 2x^2+10x-14=0
I tried 2(x^2+5x-7)=0
How are you trying to solve this? are we using the quadratic formula, are we solving for x, are we factoring? @silvernight269
Solving for x
Okay. Honestly, this can be done with the quadratic formula
Just for review, it looks like this: \[x = \frac{ -b \pm \sqrt{b^2 - 4ac} }{ 2a }\]
To make it equal to 0?
just one moment ? x_1,2 = this formule bc. there are + and - so result two roots
there are, but the roots are not exact
\(ax^2 + bx = c\) so we have to find the a, b, and c terms and then we can plug those in and solve for the various x's
So this means that a would equal 2, b =10, and c would be 14 since when you bring it to the other side, it becomes positive 14.
It still doesn’t make sense
okay. Let's try plugging everything in then
\(x_{(1,2)} = \frac{ -10 \pm \sqrt{(10)^2 - 4(2)(14)} }{ 2(2) }\)
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It would actually look more along the lines of this: x_{1,2} = \frac{ -10 \pm \sqrt{ 212 } }{ 4 }
oh, oops. Let's try that again: \(x_{1,2} = \frac{ -10 \pm \sqrt{ 212 } }{ 4 }\)
Why 212
because I'm realizing that I goofed in telling you that c = 14. It's actually -14. The reason for this is because the equation you gave was already in quadratic form and I didn't realize. It's the negative that changes the answer so drastically \(10^2 - 4 (2) (-14)\) = 212
Oooooooh
\(x_1 = \frac{ -10~+~\sqrt{ 212 } }{ 4 } = -\frac{5}{2}+\frac{1}{2}\sqrt{53}\) \(x_2 = \frac{ - 10~-~\sqrt{ 212 } }{ 4} = -\frac{5}{2} - \frac{1}{2}\sqrt{53}\)
This is what things should look like once everything is simplified, including the radicals. Does this make sense?
Kinda
What do you still have questions on?
Like, you know, where in the process?
Actually I think I’m ok
you sure?
Yea
Okay, glad to have helped!
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