In countries like USA and Canada, temperature is measured in Fahrenheit, whereas in countries like India, it is measured in Celsius. Here is a linear equation that converts Fahrenheit to Celsius:

**(i)** Draw the graph of the linear equation above using Celsius for x-axis and Fahrenheit for y-axis.

**(ii)** If the temperature is 30°C, what is the temperature in Fahrenheit?

**(iii)** If the temperature is 95°F, what is the temperature in Celsius?

**(iv)** If the temperature is 0°C, what is the temperature in Fahrenheit and if the temperature is 0°F, what is the temperature in Celsius?

**(v)** Is there a temperature which is numerically the same in both Fahrenheit and Celsius? If yes, find it.

**Solution (i)**

To draw graph of , we will find 3 or 4 set of solutions.

Putting in the equation , we get

Therefore, is one of the infinite possible solutions.

Similarly, putting in the equation , we get

Therefore, is one of the infinite possible solutions.

Putting in the equation , we get

Therefore, is one of the infinite possible solutions.

Therefore, three different solutions for equation are:

Now, we plot all these three points on the Cartesian plane. When we join these points, it makes a straight line.

**Solution (ii)**

Putting 30°C in equation, , we get

Therefore, 30°C =86°F.

**Solution (iii)**

Putting 95°F in , we get

Therefore, 95°F=35°C.

**Solution (iv)**

Putting 0°F in , we get

approximately.

Therefore, 0°F is equal to -17.8°C approximately.

Similarly, putting 0°C in , we get

Therefore, 0°C is equal to 32°F. (We can also see this in the graph shown above.)

**Solution (v)**

Yes, there is temperature which is numerically the same in both Fahrenheit and Celsius.

Putting in the equation , we get

Therefore, -40°C=-40°F.

We can also see the same thing on the graph shown above.