Knowledge Hub · Article 339 · Maths

Coordinate grid: how to plot and read points, ordered pairs (x before y, "along the corridor, up the stairs"), the four quadrants and their signs, the axes and the origin, distance between points, reflections across the axes, the midpoint, the mistakes, and printable coordinate grid paper in three sizes

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Article 339 · Maths

"Coordinate grid" is searched about 11,000 times a month in the United States, mostly by Grade 5 and 6 students and their parents looking for two things: the rules for plotting a point and a sheet of grid paper to print. This page gives both. The rules in full (the axes, the ordered pair, the three plotting steps, the four quadrants and their signs, points on the axes), then distance, reflection and midpoint for Grade 6 to 8, the mistakes, the curriculum placements, and a printable with coordinate grid paper in three sizes and a practice set.

Download the coordinate grid paper and practice (PDF) (A4, a first-quadrant 0 to 10 grid and a four-quadrant −10 to 10 grid with the rules on page 1, a 1 cm squared grid with the practice set and answers on page 2, free).

The parts of the grid

Part What it is
x-axis the horizontal number line; positive to the right, negative to the left
y-axis the vertical number line; positive up, negative down
Origin where the axes cross, the point (0, 0)
Ordered pair (x, y) the two numbers that name a point: x first (across), y second (up or down)
Coordinates the two numbers themselves; the x-coordinate and the y-coordinate
Quadrants I, II, III, IV the four regions the axes make, numbered anticlockwise from the top right
Grid lines the lines at each whole number that help you count

How to plot a point in three steps

To plot (4, 3):

  1. Put your pencil on the origin (0, 0).
  2. Move along the x-axis 4 units to the right (the first number).
  3. Move up 3 units (the second number), parallel to the y-axis. Mark the point and label it (4, 3).

To plot (−2, −5): left 2, down 5. To plot (0, 6): no move across, up 6: the point sits on the y-axis. To plot (−7, 0): left 7, no move up: on the x-axis.

The order never changes: x first, then y. "Along the corridor, then up the stairs" (British classrooms) or "run before you jump" (American) are the memory lines; "x is a cross, so x goes across" settles which letter is which.

How to read a point

Reverse the steps. From the point, go straight down (or up) to the x-axis and read the number: that is x. Go straight across to the y-axis and read the number: that is y. Write them in brackets with a comma, x first. A point 3 to the left of the y-axis and 2 above the x-axis is (−3, 2).

The four quadrants and their signs

Quadrant Where Sign of x Sign of y Example
I top right + + (3, 5)
II top left − + (−3, 5)
III bottom left − − (−3, −5)
IV bottom right + − (3, −5)

The numbering runs anticlockwise starting from the top right, the way angles are measured. Points on an axis belong to no quadrant: (0, 4) is on the y-axis, (−6, 0) on the x-axis, (0, 0) is the origin.

Grade 5 works in the first quadrant only (all coordinates positive); Grade 6 opens up all four with negative numbers.

Distance between points

  • Same horizontal line (same y): subtract the x-coordinates. From (−3, 4) to (5, 4): 5 − (−3) = 8 units. Or count the grid squares.
  • Same vertical line (same x): subtract the y-coordinates. From (2, −1) to (2, 6): 6 − (−1) = 7 units.
  • Neither (Grade 8, GCSE): draw the right-angled triangle and use Pythagoras. From (1, 2) to (4, 6): across 3, up 4, distance √(3² + 4²) = 5 units. The general formula is d = √((x₂ − x₁)² + (y₂ − y₁)²).

A rectangle with corners (−2, 1), (4, 1), (4, 5), (−2, 5) has width 6 and height 4: area 24 square units, perimeter 20. Coordinate geometry questions in Grade 6 are almost all of this shape.

Reflections across the axes

  • Reflect in the x-axis: the y-coordinate changes sign. (3, 5) → (3, −5).
  • Reflect in the y-axis: the x-coordinate changes sign. (3, 5) → (−3, 5).
  • Reflect in both (a half-turn about the origin): both change sign. (3, 5) → (−3, −5).

So the four points (±3, ±5) are the same point reflected into each quadrant, which is the Grade 6 standard 6.NS.6b in one sentence.

The midpoint

The midpoint of two points is the average of their coordinates: M = ((x₁ + x₂) ÷ 2, (y₁ + y₂) ÷ 2). Between (−2, 3) and (6, 7): ((−2 + 6) ÷ 2, (3 + 7) ÷ 2) = (2, 5). Used from Grade 8 and in GCSE for the centre of a line segment and the centre of a circle from a diameter.

The mistakes that cost marks

  • Swapping x and y: (2, 5) plotted at (5, 2).
  • Starting from the corner of the paper instead of the origin.
  • Counting lines instead of gaps (the first grid line after 0 is 1, not 2).
  • Missing a negative sign in quadrants II, III and IV.
  • Writing the pair without brackets or without the comma.
  • Numbering quadrants clockwise. It is anticlockwise from the top right.
  • Choosing an uneven scale on a hand-drawn grid: every gap on an axis must be the same size.

Where it sits in each curriculum

Curriculum When What is expected
US Common Core Grade 5 (5.G.1, 5.G.2: the first quadrant, plot and interpret points), Grade 6 (6.NS.6, 6.NS.8: all four quadrants, reflections, distances on a line), Grade 8 (8.G.8: distance by Pythagoras) first quadrant in Grade 5, four quadrants in Grade 6
England Year 4 (first quadrant), Year 6 (all four quadrants, reflections and translations), KS3 and GCSE (straight-line graphs, midpoints, Pythagoras) the four quadrants by the Year 6 SATs
Australia Year 5 (first quadrant), Year 6 (all four quadrants), Year 7 (Cartesian plane and linear graphs) four quadrants in Year 6
India (CBSE) Class 9 (Coordinate Geometry: the Cartesian plane, quadrants, plotting), Class 10 (distance and section formulas) full plane from Class 9

Practice (answers in the PDF)

  1. Plot and label A(2, 4), B(−3, 4), C(−3, −1), D(2, −1). What shape is ABCD, and what is its area?
  2. In which quadrant is each point: (−4, 7), (5, −2), (−1, −9), (6, 3)? Which quadrant is (0, −5) in?
  3. What is the distance from (−6, 2) to (3, 2)?
  4. Reflect (−4, 7) in the x-axis, then in the y-axis. Give both results.
  5. Find the midpoint of (−5, 2) and (3, −6).
  6. A point is 4 units left of the y-axis and on the x-axis. Write its coordinates.

Download the grid paper and the practice set (PDF)

Where to get help

A 1-on-1 online maths class with a tutor who holds a master's in mathematics and teaches US Grades 5 to 8, KS2 and KS3, the Australian Years 5 to 7 and CBSE Class 9 and 10 every week: the coordinate plane taught with a shared grid on screen, every point plotted by the child and read back, so the x-before-y habit sets before straight-line graphs begin. The Grade 6 maths page lists the units; the free 30-minute first class is a real lesson on this week's homework. The next pages in this set are graphing linear equations and graphing proportional relationships.

Questions parents ask

1What is a coordinate grid?
A flat surface marked with two perpendicular number lines, the horizontal x-axis and the vertical y-axis, which cross at the origin, the point (0, 0). Every point on the grid is named by two numbers, an ordered pair (x, y), that say how far across and how far up or down it is from the origin. It is also called the coordinate plane or the Cartesian plane, after René Descartes.
2How do you plot a point on a coordinate grid?
Start at the origin. Move along the x-axis by the first number (right if positive, left if negative). Then move parallel to the y-axis by the second number (up if positive, down if negative). Mark the point. For (3, −2): right 3, down 2. The rhyme "along the corridor, then up the stairs" keeps the order straight: x first, y second.
3What are the four quadrants?
The axes divide the grid into four regions, numbered with Roman numerals anticlockwise from the top right. Quadrant I: x and y both positive (+, +). Quadrant II, top left: x negative, y positive (−, +). Quadrant III, bottom left: both negative (−, −). Quadrant IV, bottom right: x positive, y negative (+, −). A point on an axis is in no quadrant.
4Which number comes first in an ordered pair?
The x-coordinate (horizontal) comes first, then the y-coordinate (vertical): (x, y). The point (2, 5) is 2 across and 5 up; the point (5, 2) is 5 across and 2 up, a different place. Swapping them is the single most common mistake, and "x is a cross, so it goes across" is the usual reminder.
5How do you find the distance between two points on a coordinate grid?
If the points share a y-coordinate (same horizontal line), subtract the x-coordinates: from (−3, 4) to (5, 4) is 5 − (−3) = 8 units. If they share an x-coordinate, subtract the y-coordinates. If they share neither, use Pythagoras: distance = √((x₂ − x₁)² + (y₂ − y₁)²), which is a Grade 8 and GCSE method.

See how we teach this, 1-on-1 online →

written by

Shobha

Founder and lead tutor, Science with Shobha

Teaching maths, science and English to children online since 2018. 500+ students, 20+ tutors, families in nine countries.

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