BCoT Maths
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Straight line graphs

All straight lines take the form of y = mx + c. Where m is the gradient (steepness) and c is the y-intercept (cuts the Y axis). 
Table of Values
​
•Use a table for values of ‘x’ to generate coordinates with ‘y’.
•A straight line through these points creates the graph of the equation.

Example 1: Draw the graph of y = 2x - 5

​Let's use value of x from 1 to 5.

When x = 1
           y = 2 x 1 - 5
           y = 2 - 5 = -3
When x = 2
            y = 2 x 2 - 5
            y = 4 - 5 = -1
When x = 3
           y = 2 x 3 - 5
           y = 6 - 5 = 1
When x = 4
            y = 2 x 4 - 5
            y = 8 - 5 = 3
When x = 5
           y = 2 x 5 - 5
​           y = 10 - 5 = 5
If you're still not sure, have a look at this video where I explain the process of how we create the table, work out the y-intercept and plot the graph.
Working out the y-intercept
Plotting the graph

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