When two variables are related linearly, plotting their values results in a straight line. This straight line of best fit can be used to add or subtract linear relationships, whether the lines are parallel or non-parallel. Vectors can be added by treating the linear lines of best fit for each variable as vectors, with the resultant vector representing their sum.

1. Form 5: Linear Law 2.1 Line of Best Fit - Drawing lines of best fit If x and y are two variables related linearly , then when the values of y are plotted against the values of x, a straight line is obtained. Graph of y against x

2. How is it related to the topic vector in the subtopic of addition and subtraction? Look at the next slide so that you can see the connection.

3. Connection When we have two lines of best fit, we can add or subtract the lines. If the lines are linear, they can be added or subtracted whether they are parallel or non-parallel to each other.

4. Line of best fit The two diagrams show the line of best fit. These two lines are parallel to each other. P Q R S

5. We have the vector and . When we add both vectors, the resultant vector is . Where,

6. Point To Be Noted Students should know the basic concept of vector which needed the concept of line of best fit. This means that the lines involved in the topic vector should be the linear lines and it is not necessarily parallel. It can be non- parallel.