Respostas

2013-07-15T23:28:20-03:00
Tc - Tf = 20

Tc = 20 + Tf

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Tc/5=Tf-32/9

20 + Tf / 5 = Tf - 32/9

180 + 9Tf = 5Tf - 160

340 = -4Tf

Tf = 340/-4

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Tf = -85°F.
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Substituindo o valor e testando o exercicio.

Tc/5 = Tf-32/9

Tc/5 = -85-32/9

Tc/5 = -117/9

Tc/5 = -13

Tc=  -13*5

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Tc= -65°C
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