Graph is actually a diagrammatic representation of a function. It can also be defined as pictorial view of dependent (output) and independent (input) values.
Straight line equation is normally given by following expression:
y = m x + c,
In above Straight Line equation, 'y' is dependent variable, 'x' is independent variable, 'm' is known as Slope and c is called as y- intercept. Also ‘c’ can be defined as the distance from origin on y- axis. Now we will discuss how to describe graph?
Various parameters of line equation are shown in above graph. Consider two points A and B with coordinates (x (1), y (1)) and (x (2), y (2)) respectively. When x = 1 then y = m + c, when x = 2, y = 2m + c and so on. Thus we can conclude that x, y is also increasing.
Slope ‘m’ is given as Ratio of coordinates of Point B to coordinates of point A. Mathematically,
Slope m = d y / d x,
Where d y = y (2) – y (1) and d x = x (2) – x (1),
Hence, m = y (2) – y (1) / x (2) – x (1),
When angle is ‘a’, then slope ‘m’ is equals to tan (a).
Mathematically, slope m = tan (a).
Constant ‘c’ is known as intercept of 'y'. It is calculated from origin. Above graph shows, when value of 'x' increases, 'y' also increases and thus an increasing graph is obtained. Point ‘o’ is known as origin. Origin can also be defined as Intersection point of x and y- axis. Coordinates of origin are (0, 0).