Construct and Calculate Rectangles
Construct a Rectangle 2 - using perp & par

1. Generate side lengths

• Click on the New Dimensions button (and wait 2 secs).  

   

REMEMBER: You can always click on undo (top right) to undo your last action.

2. Make the base of your rectangle.

• Click on Seg-Length "Segment with given length from point" icon.

• Then click on the point A (it will glow) and In the box type the number of the base of your rectangle. Hit Enter.

3-4. Draw the sides of the rectangle. Remember, the base and sides of a rectangle are perpendicular.

• Click on perpendicula "Perpendicular line" icon.

• Click on point A, then on line AB.

• Click on point B, then on line AB.

5. Now we need the point on the left line that is the height of the rectangle so we draw a circle with center A and radius the height of the rectangle. The intersection between the circle and the line is the point we need.

• Click on Circle_rad "Circle with center and radius" icon. Click on A and then type in the value of the height of your rectangle.

Click on Intersect "Intersect two objects" icon and then click on the line and then on the circle (they will glow).

6. Draw the top of the rectangle. Remember, the top and base are parallel.

• Click on parallel "Parallel line" icon. Click on point C, then on line AB.

• Click on Intersect then on top line and then right side.

7. Close your rectangle ACDB.

• Click on Segment "Segment between two points" icon. Click on A and C. Click on C and then D. Click on D and then B.

8. Clean up

9. Notice how much shorter this construction was than the previous!

10. Play with your rectangle.

• Click and drag any blue point (A moves the rectangle, B rotates the rectangle). Notice that the rectangle itself never changes since it is completely defined by the length of the two sides and the 90° angles.

• Click on Reset to start over.

                    
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