Coordinates and graphs
Plotting (x, y) and reading values from straight-line and other graphs.
KS3 builds on KS2 coordinates: read values, plot points, draw straight-line graphs from a table, find intersections by inspection. y = 2x + 1 means: pick x-values, calculate y, plot, join.
Worked examples
(2, 5) on the grid: 2 right, 5 up from origin.
y = 3x: x=0 → y=0; x=1 → y=3; x=2 → y=6. Straight line through origin.
Intersection of y = x + 1 and y = −x + 5: (2, 3).
Frequently asked questions
Use a ruler — always?
Always for straight-line graphs. Marks deducted in tests for free-hand.
How does (x, y) order matter?
x first, then y. Reading or plotting backwards is the most common Year 7 mistake.