solve by completing the square 0=6x2+5x-5
5=6x^2+5x 5=x(6x+5) how can I go about from here?
instead of rearranging you could have solved for x by using the quadratic equation do you know it?
6x^2+5x-5=0?
sorry I tried but there was nothing to factor for... usually this becomes something like (x+/- something)(x+/- something)=0
and if its the one with the weird suare rooting 4ab something I didn't learn that, and I would appreciate it if yu can show me the formula. I was sick the day the teacher taught it, and she told me to "ask my friends" or "look it up"
yeah I meant the weird one which you didn't learn so we can go through it together
I would greatly appreciate that... having a test after the break and I'm kind of screwed
ok the formula is\[\frac{ -b pm sqrt{b^{2}-4ac} }{ 2a}\]
well given the fact you are asked to use completing the square that's what you should do divide every term by 6 \[x^2 + \frac{5}{6}x = \frac{5}{6}\] find half the coefficient of x and then square it... add it to both sides of the equation... then you will have a perfect square on the left.
the system is playing up on my end but you can figure out the formula on line
so if the value of a is 6 and b is 5 and c is -5 you slot that into the formula
whoa what's the pm? @campbell_st I wasn't told to comple te the square, but that was the only way I thought of going since I could not factor. I should go do the other thing I'm assuming
pm is plus/minus
oh... ok not it makes more sense.. so it's (-1+/-sqrt(1-4(8)(-5))/16
sorry the problem was 0=6x^2+x-5
Here @nos since @Mariam.A since you were having trouble posting it: if the equation is: \[{ax^{2}+bx+c=0}\]\[x= \frac{-b \pm \sqrt{b^{2}-4ac}}{2a}\]
so it goes -1+/-sqrt(-1-(4(6)(-5))/12 -1+/-sqrt(-1+120)/16 -1+/-sqrt(119)/16 and -1+/-10sqrt(19)/16 -1/16+/-5sqrt(19)/8
more or less?
you messed up the b^2. your first line should be: -1+/-sqrt(1-(4(6)(-5))/12
oh so the sqrt(121) is the correct answer? then it would be 11
-1+/-11/12 -12/12=-1 10/12=5/6
yes. The equation you gave is actually factorable: \[0=6x^2+x-5\]\[0 = (6x-5)(x+1)\]
<I just need to try those answers>
wow. that lost the purpose it's ok at least it teached me how to do the weird thing, and I'm actually thankful for it.
I should check my answers, but thanks for the steps on the equation :)
yes that weird thingy that you said is actually very helpful so it would be wise to learn how to do it.
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