litres of milk each week at Rs /litre and litres of milk each week at Rs /litre. Assuming a linear relationship between selling price and demand, how many litres could he sell weekly at Rs /litre? . P ( a , b ) is the mid-point of a line segment between axes.
Show that equation of the line is b . Point R ( h , k ) divides a line segment between the axes in the ratio : . Find equation of the line. .
By using the concept of equation of a line, prove that the three points ( , ), (– , – ) and ( , ) are collinear. . General Equation of a Line In earlier classes, we have studied general equation of first degree in two variables, A x + B y + C = , where A , B and C are real constants such that A and B are not zero simultaneously. Graph of the equation A x + B y + C = is always a straight line.
STRAIGHT LINES Therefore, any equation of the form A x + B y + C = , where A and B are not zero simultaneously is called general linear equation or general equation of a line . . . Different forms of A x + B y + C = The general equation of a line can be reduced into various forms of the equation of a line, by the following procedures: (a) Slope-intercept form If B ≠ , then A x + B y + C = can be written as A C or B B mx c = − ...
( ) where A C and B B m c = − = − We know that Equation ( ) is the slope-intercept form of the equation of a line whose slope is A B , and y -intercept is C B If B = , then x = C A ,which is a vertical line whose slope is undefined and x -intercept is A C (b) Intercept form