Question

Efetue as operações :
A) 11/6+3/4-1/2
B) 13/9+5/8-7/12
C) 6/7.3.9/5
D)2/5:6/7

E) 3x-y=0
-4x+y=-2

F) 2x+3y=14
-x+5y=-7

Answer 1

a)11/6 + 3/4 - 1/2 (mmc=12)
11×2 + 3×3 - 1×6
22+9-6=25

b)13/9 + 5/8 - 7/12 (mmc=72)
13×8+5×9-7×7
100

c)6/7 × 3 × 9/5 (35)
6×5×3×9×7
5670

d)2/5 / 6/7
2/5 × 7/6
14/30

e){3x-y=0
{-4x+y=-2
-1x=-2 .(-1)
x=2

f){2x+3y=14
{-x+5y=-7 ×2 -> -2x+10y=-14
13y=0
y=0 e x=7