Answer:
a. 32,2°C
b. 131 °F
c. -28,9°C
Step-by-step explanation:
We must consider the following formula:
(x-32) × 5/9 = y , where x= temperature in °F an y= temperature in °C
Then,
a) In the formula we replace x=90° F, and we have: y = (90-32)× 5/9 = 32,2 °C
b) In the formula we replace y=55° C, and we have: 55 = (x-32)× 5/9 ⇒ 55×9/5 =x-32 ⇒ x=(55×9/5)+32 = 131 °F
c) In the formula we replace y= -20° C and we have: -20 = (x-32)× 5/9 = -4°F