# In my last doubt, I asked to give a formal proof, for (-)(+)=(-). I was asked by my maths teacher in school, that how when 2 unlike signs are multiplied, why the result is a negative value. Neha ma'am answered this last time, but it was not at all satisfactory.. I wanted one of the formal proofs like Brijendra Pal sir gave me for (-)(-)=(+)..Experts may prefer to that one, to make the answer satisfactory for (-)(+)=(-)...... Shruti ma'am you answered how (-)(-)=(+).....But I asked how (-)(+)=(-)...Hope you got... What I want to ask.. .

Dear Student,

Hence using distributive law of multiplication we can prove that $\left(-\right)×\left(+\right)=\left(-1\right)$
Regards,

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Hope you got what I wanted to ask... I wanted to ask formal proof for (-)(+)=(+)... According to the question.
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no (-),(-) =(+)
(+),(+)=(+)
(-),(+)=(-)
hope it helps
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FOR EXAMPLE-  (-2) + 3 =1, BECAUSE (+ ) (-) WE HAVE TO SUBTRACT   THEN WE HAVE TO CHECK THE SIGH   AGAR BADA NUMBER HAS  + SIGN THEN  THE ANSWER SHOULD BE +VE AND IF BADA NUMBER IS - SIGN THEN THE ANSWER SHOULD  BE -VE

2   (-3)+2= -1 BECAUSE GREATER  NUMBER HAS - SIGN

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Experts please give the answer according to the context... and not give a proof saying that, when 2 different signs are multiplied it gives answer in negative. So, I won't be following the things as given by the students as they answer like this.

Briendra sir gave me answer or how(-)(-) = (+)...

In almost (almost) the same format, please give answer to (+)(-) = (-)... I told almost the format... So, please be a little specific like him... and give the proof for (-)(+) = (-)

Only the difference is that,
Brijendra sir proved (-)(-) = (+)... and if any other expert or me (Brijendra sir)  is answering he/she has to answer and proof (-)(+) = (-)...

Hope that the experts understands me...

Thanking You!
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Sorry for the inconvenience Shruti ma'am.. but I was unable to understand your answer for (-)(+)=(-).  But, when I saw it 4 to 5 times, I was able to understand your answer... Thanking you and Sorry again!!!

Sorry for the inconvenience.
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What are you looking for?