Question

Can someone please help me? thank you. ​

Answer 1

Explanation:

c(f) =
`(5)/(9)(f-32)`

`-21 = (5)/(9)(f-32)`

Multiply both sides by 9

-21*9 = 5(f - 32)

-189 = 5*f - 5*32

-189 = 5f - 160

Add 160 to both sides

-189 + 160 = 5f

-29 = 5f

Divide both sides by 5

-29/5 = f

f = -5.8

f = -6 °C