Read and plot points in all four quadrants, find midpoints, and draw straight lines from a table of values.
What you will learn
- Read and plot coordinates in all four quadrants
- Find the midpoint of a line segment, and an end point from the midpoint
- Plot y = mx + c from a table of values
- Recognise the lines x = a and y = b
Across, then up or down
A point is written (x, y).
The x coordinate says how far across from the origin, the y coordinate how far up. Left of the y-axis x is negative; below the x-axis y is negative.
P is (−3, 2): 3 left and 2 up. Q is (4, −1): 4 right and 1 down. Swapping the numbers gives a different point: (2, −3) is somewhere else entirely.
The rest of this lesson and its 7 practice questions are locked.
In this lesson
- Across, then up or down
- Midpoints: add and halve
- Tables of values and special lines
- Try it: Plot a line and check a point
7 practice questions, marked as you go; about 20 minutes in all.
In this unit: Straight-line graphs
Coordinates and midpoints, gradients and intercepts, the equation of a line, parallel and perpendicular lines, and straight-line graphs in real life.
- Coordinates, midpoints and plotting lines
- y = mx + c
- Finding the equation of a line
- Parallel and perpendicular lines
- Real-life graphs