The formula C=5/9(F-32) expresses the relationship between Fahrenheit temperature, F, and Celsius temperature, C. In Exercises 17–18, use the formula to convert the given Fahrenheit temperature to its equivalent temperature on the Celsius scale. 50 °F

Welcome back. I'm so glad you're here. We are given the equation for converting from Celsius to Fahrenheit and that is F equals 9/5 times C plus 32. That is our conversion formula. And we're also given that we're trying to convert 20 degrees Celsius to its equivalent temperature in Fahrenheit. What does that mean? Well, it means that our C value is going to be 20. So anywhere we see a C in our equation, here's a C. We are going to replace that with 20. So let's go ahead and do that. F equals R. Fahrenheit equals 9/ 20 not 9/5 see anymore. So 9/5 times plus 32. Great. On that right hand side we've got all numbers and so we can combine those so that we figure out what the Fahrenheit temperature is. And we can go through this recalling briefly from previous lessons, the order of operations where we've got parentheses first, then exponents, then multiplication and division from left to right and then addition and subtraction from left to right. So do we have parentheses? Well, there are parentheses there Around the 20 but they are indicating that there is multiplication happening. There's there's no operations happening in there. It's just a 20. So those parentheses indicate multiplication, there's telling us that 9/5 is being multiplied by 20. So we can check off parentheses and no there are no exponents. And as we just said there is multiplication happening here. 9/5 times 20. Well we can do some simplification here. Five divided by five is one in 20 divided by five is four. So now we can just multiply across the the enumerators here and nine times four is 36. So bring down this F equals 36 then bring down this plus 32. No more multiplication or division to go through. And now we've just got addition and that last part in addition and subtraction from left to right. So great. We'll just do 36 plus 32. So F equals degrees. So it's 68 degrees. Fahrenheit. I won't write that degrees there. I'll rewrite this as 68 degrees. Fahrenheit like that. We look at our answer choices and that is answer choice. C. Well done, we'll catch you on the next one.

The formula C=5/9(F-32) expresses the relationship between Fahren...

Textbook Question

In Exercises 1–14, write each number in decimal notation without the use of exponents. 3.8X10²

The formula C=5/9(F-32) expresses the relationship between Fahrenheit temperature, F, and Celsius temperature, C. In Exercises 17–18, use the formula to convert the given Fahrenheit temperature to its equivalent temperature on the Celsius scale. 50 °F

Key Concepts

Temperature Conversion

Linear Equations

Substitution

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