I obtained this form while solving an aptitude question.
3000x−50+3000x+50=11
I changed it into quadratic equation
11x2−6000x−27500=0
but I don't know how to solve it.
I can't find two factor for 303500 that sums to 6000 or when I use formula the numbers become huge...
Without using calculator
how to solve it? is there any other simple way to solve [other method]? [or finding factor] I'm a beginner in math. Please explain your answer for me.
Answer
There isn't any standard, guaranteed method apart from the quadratic formula to solve a quadractic equation. However sometimes there are "ad-hoc tricks" which might help you get one root.
The RHS of the equation is an integer; You might suspect that an x such that both the terms on the LHS are integers might be a root (this does not have to be true at all, but it's not bad to try).
Also since x−50 and x+50 differ by 100, you want a number y such that both y and y+100 divide 3000. Noticing that 500 and 600 satisfy this gives x=550 as a root.
Using this, you can find the other root quite easily to be x=−5011 since the product of the roots is −27500/11.
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