Respostas

2014-02-10T17:49:12-02:00
Tc / 5 = Tf - 32 / 9

Tc = Tf

Tf/5 = Tf - 32 / 9

9Tf = 5Tf - 160

9Tf - 5Tf = - 160

4Tf = -160

Tf = -160/4

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Tf = -40°F = -40°C
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