Question

2/7 - 3/5 (1/2 + 1/3) sobre 3/4 + 1/3 (2/5-1/4)

É pra segunda

Answer 1

Boa noite 

numerador
2/7 - (3/5)*(1/2 + 1/3) 
2/7 - (3/5)*(3/6 + 2/6)
2/7 - (3/5)*(5/6) 
2/7 - 1/2 = 4/14 - 7/14 = -3/14 

denominador
3/4 + (1/3)*(2/5 - 1/4)
3/4 + (1/3)*(8/20 - 5/20) 
3/4 + (1/3)*(3/20) = 3/4 + 1/20 = 15/20 + 1/20 =  16/20 = 4/5 

E = (-3/14)/(4/5) = (-3/14)*(5/4) = -15/56 

Answer 2

2/7-3/5=11/35
1/2+1/3=5/6
3/4+1/3=13/12
2/5-1/4=3/20

espero q ajude em alguma coisa :/