Question

efetue: A)-5/6+1/4=. B)-7/12-3/16. C)-7/9x21/5. D)-7/9:21/5

Answer 1

A) -5/6 + 1/4
tira mmc
-10+3/12 
-7/12

B) -7/12 -3/16
mmc novamente
-28 - 9/48
-37/48

C)-7/9*21/5
-7*21/9*5
-147/45

D)-7/9:21/5 
-7/9 * 5/21
-35/189