Question

11.10. The points (2, 4) and (-2,-4) are plotted on thecoordinate plane using the equation y=a.x.How can you use the coordinates to find thevalue of a?..

Answer 1

Given:

The equation of the line is y = ax.

The coordinates are given as,

`\begin{gathered} (2,4) \\ (-2,-4) \end{gathered}`

The objective is to find the value of a using the coordinates.

Step-by-step explanation:

The general formula of a straight line is,

`y=mx+b\text{ . . . . . (1)}`

Here, m represents the slope of the straight line and b represents the y-intercept.

Similarly, the general formula to find the value of slope m is,

`m=(y_2-y_1)/(x_2-x_1)\text{ . . . . . (2)}`

To find a:

By comparing the given equation with the equation (1),

`m=a`

Consider the given coordinates as,

`\begin{gathered} (x_1,y_1)=(2,4) \\ (x_2,y_2)=(-2,-4) \end{gathered}`

To find the value of a substitute the given coordinates in equation (2).