Construct the angles of the following measurements:
(i) 30° (ii) 15°
Answers
Answer:
)
1. Draw a ray OX.
2. Cut an arc from O, cut another arc of same length as OA, which intersects at B.
3. Cut two arcs from A and B which intersects at C.
4. Join O−C. ∠COA is 30
∘
.
2)
1. Draw a ray OX.
2. Cut an arc from O, cut 2 another arcs of same length as OA, which intersects as B and F.
3. Cut two arcs from B and F which intersects at C. (∠COX=90 deg)
4. In the similar way, bisect ∠COX to get DOX which is 45 deg angle and then again bisect ∠DOX to get to get EOX .
6. Join O−E. ∠EOA is 22.5
∘
.
3)
1. Draw a ray OX.
2. Cut an arc from O, cut another arc of same length as OA, which intersects at B.
3. Cut two arcs from B and A which intersects at C. (∠COX=30 deg)
4. In the similar way, bisect ∠COX to get DOX.
6. Join O−D. ∠DOA is 15
∘
.
solution
(i)We construct angle of 30° , As :-
Step 1 ) Draw a line AB .
Step 2 ) Take any radius and center " A " draw an arc that intersect our line AB at " C " .
Step 3 ) Now with same radius and center is C , we draw another arc that meet our first arc at " D ". Join AD
Step 4 ) Now we draw two arc with same radius by taking center C and D , both arc intersect at " E "
Step 5 ) We join line AE ( AE is angle bisector of ∠ BAD ) , So we get ∠ BAE = 30° .
We can verification :-
We know : ∠ BAD = 60°
And
line AE is angle bisector of ∠ BAD .
So,
∠ BAE = ∠ EAD = 30°
Here are the steps to construct an angle of measure 15°:-
Step 1 : Draw a ray OA. Now taking O as centre and convenient radius draw an arc intersecting OA at B.
Step 2: Taking B as centre and with the same radius before draw an arc intersecting the previously drawn arc at C.
Step 3 : Taking B and C as centre, draw arcs of same radius to intersect each other at D.
Now ∠AOD = 30°. Let BC intersect OD at E.
Step 4: Taking E and B as centre, draw arcs of same radius to intersect each other at F. Join OF.
Thus ∠AOF = 15°.
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