The idea, step by step
Read across, then up or down
To read a point, follow a vertical line to the x-axis to find its horizontal coordinate, then a horizontal line to the y-axis to find its vertical coordinate. Write the pair in the order (x,y), using brackets and a comma.
Use the grid scale. On this grid every interval is 1 unit, but other grids may count in twos or fives. Read the numbers before counting squares.
Plot and check
To plot a pair, start at the origin. Move left or right for x, then up or down for y, and make one clear point. Label the point slightly away from it so the mark stays visible.
Read your plotted position back as an ordered pair. If the coordinates are swapped, the point usually moves to a different place. Plotting (3,2) means 3 right and 2 up, not 2 right and 3 up.
A common trap
Reversing the coordinates because the vertical direction is noticed first.
Instead: Use x before y: horizontal position first, vertical position second.
See the thinking
Read point A
Read the coordinates of A on the grid.
- A is 4 units left of the origin, giving x = −4.
- A is 1 unit above the origin, giving y = 1.
Plot a point
Plot C = (3,2).
- Start at (0,0).
- Move 3 units right, then 2 units up.
- Mark and label the intersection C.
Check your understanding
A point is 2 units left and 4 units up from the origin. Give its coordinates.
Show answer
(−2,4)
Left gives a negative x-coordinate; up gives a positive y-coordinate.
Your turn
6 questions · 11 marks · Work at your own pace.
Read the questions online
- Read the coordinates of B on the grid.1 mark
- Plot P = (−2,4) on the grid.2 marks
- Plot Q = (4,−1) on the grid.2 marks
- Plot P = (−3,−2), Q = (1,−2) and R = (1,2). Join P to Q, Q to R and R to P.3 marks
- For (2,−4), Sam moves 4 units left and 2 units up. Explain and correct the plotting error.2 marks
- Give the coordinates of a point on the x-axis 5 units left of the origin.1 mark
Read the worked solutions
Equivalent correct methods earn the corresponding marks. Include units where asked.
- Read the coordinates of B on the grid.1 mark
B is 2 right and 3 down from the origin.
(2,−3) - Plot P = (−2,4) on the grid.2 marks
Use x = −2, then y = 4.
P is 2 left and 4 up from the origin. - Plot Q = (4,−1) on the grid.2 marks
Use x = 4, then y = −1.
Q is 4 right and 1 down from the origin. - Plot P = (−3,−2), Q = (1,−2) and R = (1,2). Join P to Q, Q to R and R to P.3 marks
P and Q share y = −2.
Q and R share x = 1.
Join the vertices in the stated order.
The three points form a triangle with a horizontal side PQ and a vertical side QR. - For (2,−4), Sam moves 4 units left and 2 units up. Explain and correct the plotting error.2 marks
The first coordinate, 2, is the horizontal move.
The second coordinate, −4, is the vertical move.
Sam used the wrong direction and swapped the values. Move 2 right and 4 down. - Give the coordinates of a point on the x-axis 5 units left of the origin.1 mark
Five left gives x = −5.
On the x-axis, y = 0.
(−5,0)
Curriculum reference & lesson scope
Australian Curriculum v9 / SA Curriculum Mathematics
Year 6 four-quadrant Cartesian coordinates, plotting and reading points, and coordinate changes.
Official curriculum source ↗