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#### yanna.banana

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« on: June 27, 2016, 04:23:22 PM »
can someone give me a step by step walk through of this

here is my equation 0=x^​2​​ +6.3*10^​−8x−1.0*10^−14
the answers are 7.3*10^-8 and -1.4*10^-7
i keep obtaining
6.3*10^-8 +/- 2.01*10-7 divided by 2 giving me
2.64*10^-7 and -1.38*10^-7
​​

#### Borek

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« Reply #1 on: June 27, 2016, 05:50:59 PM »
6.3*10^-8 +/- 2.01*10-7 divided by 2 giving me
2.64*10^-7 and -1.38*10^-7​

No way to reproduce these numbers. I suspect you are misusing your calculator.

Note: the correct formula calls for -b, not b (so (-6.3×10-8±2.10×10-7)/2).
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#### yanna.banana

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« Reply #2 on: July 01, 2016, 11:27:44 AM »
okay then it must be a copying error my issue is i never am able to solve this quadratic properly.
i have  right now (for a different question)
0= x^2-1.74*10^-6 + 10^-4.76x

i am obtaining  +4.17*10^-3 and - 4.17*10^-3 and it is not correct.
Can someone show me a step by step?
thanks it would be so helpful.. i think the scientific notation is throwing me off. as i can solve with regular numbers

#### mjc123

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