SOLUTION: Add -4/5 + (-3/4) I do not understand this question at all if someone could please explain to me. I simply do not understand how to add the already minused numbers I guess. I t

Algebra ->  Trigonometry-basics -> SOLUTION: Add -4/5 + (-3/4) I do not understand this question at all if someone could please explain to me. I simply do not understand how to add the already minused numbers I guess. I t      Log On


   

Question 115223: Add -4/5 + (-3/4)
I do not understand this question at all if someone could please explain to me. I simply do not understand how to add the already minused numbers I guess. I think that is my problem other than being confused.
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
Solved by pluggable solver: Fractions Solver


-4%2F5%2B-3%2F4 Start with the given expression




In order to add these two fractions, these fractions need to have a common denominator.


In order to do that, we simply find that the LCM of 5 and 4 is 20 (note: if you need help with finding the LCM, check out this solver)


Now we need to get each denominator to 20



%284%2F4%29%28-4%2F5%29%2B-3%2F4 Multiply -4%2F5 by %284%2F4%29


-16%2F20%2B-3%2F4 Multiply -4%2F5 and %284%2F4%29 to get -16%2F20



-16%2F20%2B%285%2F5%29%28-3%2F4%29 Multiply -3%2F4 by %285%2F5%29


-16%2F20%2B-15%2F20 Multiply -3%2F4 and %285%2F5%29 to get -15%2F20



Since both fractions have a common denominator of 20, we can now combine the fractions


%28-16%2B-15%29%2F20 Combine the fractions


-31%2F20 Add the numerators



So

-4%2F5%2B-3%2F4=-31%2F20