Question 159238
let f represent degrees in fahrenheit scale.
let c represent degrees in celsius scale.
{{{f = (9/5)*c + 32}}}
solve for c
{{{(9/5)*c = f - 32}}}
this is the same as {{{(9*c/5) = f -32}}}
{{{9*c = 5*(f-32)}}}
{{{c = (5*(f-32)/9)}}}
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fahrenheit ranges from -85 degrees to +50 degrees.
-85 degrees in celsius = {{{(5*((-85)-32))/9}}}
this becomes {{{(5*(-117))/9}}}
this becomes -65 degrees celsius.
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+50 degrees in celsius = {{{(5*((+50)-32)/9)}}}
this becomes {{{(5*(18))/9}}}
this becomes 10 degrees celsius.
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-85 degrees fahrenheit to +50 degrees fahrenheit becomes
-65 degrees celsius to 10 degrees celsius.
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to prove the answer, solve back to fahrenheit.
-65 degrees celsius * 9/5 = -117 + 32 = -85 degrees fahrenheit
+10 degrees fahrenheit * 9/5 = 18 + 32 = 50 degrees fahrenheit.
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conversion back to fahrenheit checks out.
answer is -65 degrees celsius to 10 degrees celsius.