$A$ line is perpendicular to the line $ax + by + c = 0$ and passes through $(a, b)$. The equation of the line is

The owner of a milk store finds that he can sell $980$ liters of milk each week at Rs $14$ per liter and $1220$ liters of milk each week at Rs $16$ per liter. Assuming a linear relationship between selling price and demand,how many liters could he sell weekly at Rs $17$ per liter?

$A$ line passes through $(x_{1}, y_{1})$ and $(h, k)$. If the slope of the line is $m$,show that $k - y_{1} = m(h - x_{1})$.

If the line $y = mx + c$ passes through the points $(2, 4)$ and $(3, -5)$,then:

If each of the points $(a, 4)$ and $(-2, b)$ lies on the line joining the points $(2, -1)$ and $(5, -3)$,then the point $(a, b)$ lies on the line:

The equation of a line,whose perpendicular distance from the origin is $5$ units and the angle,which the perpendicular to the line from the origin makes,is $210^{\circ}$ with the positive $X$-axis,is