From previous activities, we know that we can recognise the equation of a straight line graph.
It is in the form: y = mx + c
Where m is the gradient (steepness) of the line
and c is the y-intercept (where the line crosses the y axis)
Parallel Lines
In order for a line to be parallel to another then the steepness (gradient) must be the same.
The y-intercept does not matter in this case.
You can see from the lines here that they are parallel as they have the same gradient.
This activity is about recognising lines that are parallel to each other.
Example
Which of these lines are parallel?
y = 4x - 3 y - 4x = 7 y = 2x - 3
Answer
To be parallel the lines have to have the same gradient.
In this case, once they are all in the same form, then the first two have a gradient of 4 so are parallel.
Let's try some questions - remember they all have to be in this form: y = mx + c