1.Geometrical Constructions / 7 th /Mathematics
Practice Set 1 | Q 1.1 | Page 2
Draw the line
segment of the length given
below and draw their
perpendicular bisectors.
5.3 cm
Solution: Step of construction:
1. Draw line segment
AB = 5.3 cm.
2. With A as
center and radius
more than half
of AB, mark two
arcs, one above
and other below the line
AB.
3. With
B as a centre
and same radius,
draw two arcs cutting the
previous drawn arcs and name
the point of
intersection as X
and Y.
4. Join XY and na me
the point where this line cuts
AB as point
P. XY is the perpendicular bisector
of AB.
Practice Set
1 |
Q 1.2 | Page
2 Draw the line
segment of the length given
below and draw their
perpendicular bisectors. 6.7 cm
Steps of
construction:
1. Draw line segment
CD = 6.7 cm.
2. With C as
center and radius more
than half of
CD, mark two arcs,
one above and other
below the line CD.
3. With D as
a centre and
same radius, draw two
arcs c and name the
point of intersection
as A and B.
utting the previous drawn arcs
4. Join
AB and name the point
where this line cuts CD as point
Q. perpendicular bisector of CD.
Practice Set
1 |
Q 1.3 | Page
2 AB
Draw
the line segment
of the length given below
and draw their perpendicular bisectors. 3.8 cm
Solution: Step s
of construction:
1.
Draw line segment XY =
3.8 cm.
2.
2. With X as
center and radius
more than half
of XY, mark two
arcs, one above
and other below the line
XY.
Practice Set
2 |
Q 1.2 | Page
4
Draw triangle
with the measures given In
∆ STU, Solution: l(ST) = 7 cm, l(TU) =
4 cm,
Steps of
construction:
1. Draw
a line
ST = 7 cm below. l(SU) = 5 cm
2. With
S as centre and
5 cm as
the radius, draw an
arc above the
line ST.
3. With
T as the center
and 4 cm
as the radius,
draw an arc cutting the
previous drawn arc at point
U. 4. Join US
and UT. ∆STU is thus the required
triang le.
Practice Set 2 |
Q 1.3 | Page
4
Draw triangle with the
measures given In ∆ PQR, l(PQ) = 6 cm,
l(QR) = 3.8 cm, below. l(PR) = 4.5
cm
Solution: Steps of
construction:
1. Draw a line
PQ = 6 cm
2. With
P as centre and
4.5 cm as the radius,
draw an arc above the
line PQ.
3. With Q as
the center and 3.8 cm
as the radius, draw
an arc cutting drawn arc at
point R.
4. Join RP
and RQ. ΔPQR is thus the required
triangle.
Practice Set 2
| Q 2
| Page 4
Draw an equilateral
triangle with side
6.5 cm
2. With
B as a centre
and 6.5 cm
as radius, draw an
arc above the line
BC.
3. With C
as a
centre and 6.5
cm as radius,
draw an arc cutting the
previous drawn arc.
