Okay so just starting algebra this year, and came upon the question: x + 4/7 = 3/8

and the answer is - 11/56....where did the negative come from?? and why is it negative and not posotive?? please help!!! and remember i'm only starting algebra please explain in simplest terms possible

Sprung09

Try thinking about it knowing what relation the 56 has with the 7 and 8? Then think about creating common denominators for all the fractions from there? Let me know if this gets you anywhere.

Kaykay09

I am able to find the answer ok, I just don't understand why it is a -(negative)... I don't see where the - sign fit in....

Sprung09

The answer fraction would be negative becuase when you change all the fractions to common denominators it would make the 4 and 3 greater than they are now. Making the fractions that they give you in the equation would creater greater fractions than the -11/56? Does this help at all?

KeepItSimpleStupid

x= 3/8 - 5/7 ; rewriting

5/7 = ~.0.57
.......(use google as a calculator - just type 5/7 in the google search bar)
3/8= 0.375

X ~= 0.375 - 0.57 ;3/8 is smaller than 5/7

Now do you see where the negative sign comes from

PS: That isn't the way to do the problem because of the aproximations.

KeepItSimpleStupid

Hey, I have to own up to my reputation once and a while. You can't readily tell if one is bigger than the other one at this stage in development.

Kaykay09

wow! thanks guys!! yeah those answers totally helped me out alot..... i get it now....since 3/8 is smaller than 4/7 that means that it would be a negative...gracias!!

KeepItSimpleStupid

You can easily tell that when the common denominator is 8 * 7 or 56