Construct and Calculate Rectangles
Construct a Rectangle 1

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. A rectangle has a 90° angle with its base.

• Click on Angle-Size "Angle with given size" icon.

• Click on point B, then on point A and erase 45 and type in 90. Leave the °! Hit Enter. (If you erase the degree sign, you can get another by clicking on the arrow to the right of arrow.

4. Draw a line through A and C.

• Click on Line2pt "Line through 2 points" icon.

• Click on A and then C.

5. Now we need the point on this 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. Now do 3-5 on the top side of your rectangle.

• Click on Angle-Size, then on A and then on D. Erase 45 and type in 90. Leave the °. Hit Enter.

• Click on Line2pt, then on D and then on E.

• Click on Circle_rad, then on D and type in base number.

• Click on Intersect then on line and then on the circle.

7. Close your rectangle ADFB.

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

8. Clean up

9. 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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