Write the following as an equation in two variables: $8 y - 15 = 0$.

If the temperature of a liquid can be measured in Kelvin units as $x^{\circ} K$ or in Fahrenheit units as $y^{\circ} F$,the relation between the two systems of measurement of temperature is given by the linear equation
$y = \frac{9}{5}(x - 273) + 32$
$(i)$ Find the temperature of the liquid in Fahrenheit if the temperature of the liquid is $313^{\circ} K$.
$(ii)$ If the temperature is $158^{\circ} F$,then find the temperature in Kelvin.

The linear equation that converts Fahrenheit $(F)$ to Celsius $(C)$ is given by the relation:
$C = \frac{5F - 160}{9}$
$(i)$ If the temperature is $86^{\circ} F$,what is the temperature in Celsius?
$(ii)$ If the temperature is $35^{\circ} C$,what is the temperature in Fahrenheit?
$(iii)$ If the temperature is $0^{\circ} C$,what is the temperature in Fahrenheit? And if the temperature is $0^{\circ} F$,what is the temperature in Celsius?
$(iv)$ What is the numerical value of the temperature which is the same in both the scales?

Solve the equation $2y + 1 = y + 4$ and represent the solution$(s)$ on $(1)$ the number line $(2)$ the Cartesian plane.

Find the solution of the linear equation $x + 2y = 8$ which represents a point on:
$(i)$ $x$-axis
$(ii)$ $y$-axis

Determine which of the given equations is represented by the graph shown in the figure below.