Question

Construct with ruler and compasses, angle of the following measure:
${90}^o$

Answer 1

Step 1: A ray $OA$ is drawn.

Step 2: An arc from $A$ is drawn with the same length as $OA$

Step 3: An arc from $B$ is drawn with the same length as $OB$

Step 4:Construct a perpencicular bisector to the arc from $B$ to the another arc.Join $OC$

$\therefore \angle AOC={90}^{\circ }$

Thus,$\angle AOC$ is the required angle making ${90}^{\circ }$