Question

construct an angle of 90° with using scale and compass

Answer 1

Follow the following step to construct 90 Degree Angle 

1). Use ruler and draw a Line segment OB of any convenient length. (as shown below) 



2). Now use compass and open it to any convenient radius. And with O as center , draw an arc which cuts line segment OB at X. (as shown below) 



3). Again use compass and opened to the same radius (as of step 2). And with X as center , draw an arc which cutsfirst arc at D . (as shown below) 



4). Again use compass and opened to the same radius (as of step 2). And with D as center , draw another arc which cuts first arc at C . (as shown below) 



5). Again use compass and opened to the same radius (as of step 2). And With C & D as center , draw two arc which cuts each other at E . (as shown below) 



6). Join OE and extent it to A . (as shown below) 



7). Above formed angle AOB = 90 Degree. 

Answer 2

1.Draw a line segment AB.
2.Measure half of the length of the line segment by compass.
3.From point A draw an arc cutting AB at C.
4.Now from point C draw an arc cutting the previously drawn arc at D.
5.Now from point D draw an another arc cutting the previously drawn arc at E.
6.Now put the compass on point D and draw an arc.
7.Again from point E,draw an another arc intersecting the previous arc at F.
8.Now join A and F.
....Ur 90 degree angle is ready...