Construction 90* and 45*

Introduction: Construction 90* and 45*

In this ill show you how to construct an angle 90* and 45*

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Step 1: Things You Need

A paper ,scale, pen, compass,pencil

Step 2: Base

Draw a base of any length B and C

Step 3: Arc

With compass on one end (B) Draw an arc of any radius(usually not much big arc)

Step 4: Arcs

With same radius of the previous arc draw another arc { Compass on the first arc end on the base And With same radius} Draw another arc {Compass on the previous arc And with Same radius}

Step 5: Arcs Up Above

With Compass points on the last two arcs Up above Like that bothe the arcs above bisects each other

Step 6: Join

Join the lines to the arcs bisected and there you go 90* JOIN B and A

Step 7: Bisector

To draw am angle bisector from the first arc drawn at B ,draw an arc

And from the line AB cuted by the first arc in the second pic draw an arc which bisects the last one

Step 8: Join

Join B to D and you got an angle bisector or a 45*

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    2 Discussions


    3 years ago

    Step 1 - Get a camera that doesn't take blurry images lol. ;)


    3 years ago

    you need to note that is not an accurate way to draw a right angle.

    If you draw a complete circle with a center at the end of the line, then find the intersecting points in it all the ways round as you did the first two you will see that you will make 6 marks and there will be some left before getting back to where the line intersects the circle.

    The reason is you are using the radius of the circle to measure the angles around the circle and not taking into account pi (3.14).

    if you want to see how immaculate this method is, just extend your line all the way through the circle and repeat your process from the other side. You will end up with 2 lines originating from the center of the circle and diverging up.