Drawing and completing on the square grid
Primary 4 drawing on a square grid: complete rectangles and squares using equal opposite sides and right angles, including figures that are tilted.
Questions in this lesson
Transcript
The grid below shows the points A, B and C of Rectangle A B C D. The sides A B and B C are already drawn. Mark the point D on the grid and complete the rectangle. Try it first. Pause if you like. Count the move from B to C. One, two, three, four. That is four squares up. Opposite sides of a rectangle are parallel and equal. So from A, count the same move, four squares up. One, two, three, four. Mark that point D. Draw A D, from dot to dot. Then draw D C to close the rectangle. D C is the same move as A B, five squares to the right. So D is four squares directly above A.
The grid below shows the points A, B and C of Square A B C D, with the sides A B and B C drawn. Mark the point D on the grid and complete the square. Try it first. Pause if you like. Count the move from B to C. One, two squares to the right. Then one, two, three squares down. Opposite sides of a square are parallel and equal. So from A, count the same move. One, two squares to the right. Then one, two, three squares down. Mark that point D. Draw A D, from dot to dot. Then draw D C to close the square. Check: D to C is three squares to the right and two squares up, the same move as A to B. So from A, D is two squares to the right and three squares down. Opposite sides of a rectangle or a square are the same move, so count the move and repeat it.