Question

where C is degrees Celsius
Find the temperature in degrees Fahrenheit (to the nearest degree) if it is 17 °c outside.

f(c) = 9/5c + 32

can someone help me with this I was never that great in math

Answer 1

Just substitute 17 into the "c" variable, and perform the equation.

Answer 2

okay that's what I was thinking but not for sure

Answer 3

If it has an addition sign, then you substitute the Celsius.
If it has a subtraction sign, then you substitute the Fahrenheit.

Answer 4

so your saying like for example since this problem has a + I just put - instead ?

Answer 5

Nope.
There are two equations:
T(f) for eval. the temp. in Fahrenheit, and T(C) for eval. the temp. in Celsius.
One has addition sign, and the other has subtraction sign.
They aren't the same equations, though.

Answer 6

oh okay like can you show me a example of what you mean?

Answer 7

The two formulas for temperature:

From Fahrenheit to Celsius:\[T(F)=\frac{ 9 }{ 5 }C+32\]From Celsius to Fahrenheit:\[T(C)=\frac{ 5 }{ 9 }(F-32)\]Notice which equation has a plus sign and which has a minus sign.
Plus means you're increasing the value which means you're converting Celsius to Fahrenheit (Since e.g. 10.00 °C = 50 °F).
Minus sign means you're decreasing which means you're converting Fahrenheit to Celsius (Since e.g. 50 °F = 10.00 °C).
The wisdom is: If it has a plus sign, then you substitute the Celsius. If it has a minus sign, then you substitute the Fahrenheit.