Question

calcule a) 1/2+3/7
b)-2/3+4/9
c) 5/3+(-1/3+(-1)

Answer 1

$\frac{1}{2} + \frac{3}{7}$

Tira MMC entre 2 e 7 que é 14.

$7 + 6 = 13$

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$\frac{ - 2}{3} + \frac{4}{9} = - 18 + 12 = - 6$

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$\frac{5}{3} + ( \frac{ - 1}{3} + ( - 1)) = \frac{5}{3} - \frac{1}{3} - \frac{1}{1} \\ 15 - 3 - 9 = 3$

Answer 2

Resposta:

Explicação passo-a-passo:

a)

= 1/2+3/7

MMC (2,7) = 14

= (7.1+2.3)/14

= (7+6)/14

= 13/14

b)

= -2/3+4/9

= [3.(-2) + 1.4]/9

= [-6 + 4]/9

= - 2/9

c) 5/3+[ -1/3+(-1)]

= 5/3 + (- 1/3 - 1)

= 5/3 - 1/3 - 1

= 5/3 - 1/3 - 3/3

= 4/3 - 3/3

= 1/3