how do you do 8*7(-6)

Actually... It really depends... There are many reasons why you would place brackets. Either to tell it is multiply should we determine that there is an invisible Mutiply sign or the fact that the number is a negative. I know the answer should be my first Answer -336 but, if you keep revising it, you may interpret it as that.

it =90

So we would do 8*7(-6) like

8*7(-6)          ( now here we just simply have to multiply the three of then and as -6 is in brackets just beside 7 that is why we are multiplying that and now just multiplying the three of them would give is our answer and as 6 has a minus sign even out answer will include that)

= -336     ANSWER

$${\mathtt{8}}{\mathtt{\,\times\,}}{\mathtt{7}} = {\mathtt{56}}$$

Then we MULTIPLY that with (-6)

$${\mathtt{56}}{\mathtt{\,\times\,}}\left(-{\mathtt{6}}\right) = -{\mathtt{336}}$$

^Update. I don't know how I got that....

Or you do it as

$${\mathtt{8}}{\mathtt{\,\times\,}}{\mathtt{7}} = {\mathtt{56}}$$

then you Subtract 6

$${\mathtt{56}}{\mathtt{\,-\,}}{\mathtt{6}} = {\mathtt{50}}$$

I believe rosala's answer would be correct...if the parentheses weren't there.

The parantheses make me think we want to multiply this out because of the distributive property.

8*7(-6)

this really becomes

8*7*(-6)

and now we just multiply it out

56*(-6)

-336

Yer... This question is a little badly worded. 

No takahiro this question isn't badly worded its just is who are so confused and so have done a slight mistake! I have corrected mine and y don't u correct yours ! And ninja has already given a superb answer!

It's really how you interpret it...

I checked the calculator and it gave the answer as -336.

I would agree both answers are correct...based on the context. The question is a little ambiguous.

Yes u both are right this question is a lil tricky! And I too think the correct answer is -336 becoz IF the asker would want us to subtract then he or she would not have placed the brackets and just simply placed -6.

Editing answers to make them correct is good but if you think someone may have seen your wrong or different answer you should state that an edit has been done. (Takahiro did this)  

Otherwise people get confused - they think that they have been seeing things.