Chapter 4 PRACTICAL GEOMETRY
Exercise 4.1
Q.1 Construct the following quadrilaterals.
(i) Quadrilateral ABCD.
AB = 4.5 cm
BC = 5.5 cm
CD = 4 cm
AD = 6 cm
AC = 7 cm
Sol. Step 1: Construct ΔABC using SSS criterion.
Step 2: Keep A as centre and draw an arc of radius 6 cm on the opposite side of point B.
Step 3: Draw an another arc keeping centre as C of radius 4 cm, such that it intersects the arc drawn in the above step. The intersecting point of both the arcs will be point D.
To complete the quadrilateral ABCD, join points A and C to D.
(ii) Quadrilateral JUMP
JU = 3.5 cm
UM = 4 cm
MP = 5 cm
PJ = 4.5 cm
PU = 6.5 cm
Sol. Step 1: Construct ΔJUP using SSS criterion.
Step 2: Keep P as centre and draw an arc of radius 5 cm on the opposite side of point J. Draw an another arc keeping centre as U of radius 4 cm, such that it intersects the previous drawn arc. Let the point of intersection be M.
Step 3: To complete the quadrilateral JUMP, join points P and U to M.
(iii) Parallelogram MORE
OR = 6 cm
RE = 4.5 cm
EO = 7.5 cm
Sol. Step 1: Construct ΔEOR using SSS criterion
Step 2: Take O and E as centres with arcs of radius 4.5 cm and 6 cm. These two arcs must intersect and this is the point M.
Step 3: To complete the parallelogram MORE, join O and E to M.
(iv) Rhombus BEST
BE = 4.5 cm
ET = 6 cm
Sol. Step 1: Construct ΔBET using SSS criterion
Step 2: Keep E as centre and draw an arc of radius 4.5 cm on the opposite side of point B. Draw an another arc keeping centre as T of radius 4.5 cm, such that it intersects the previous drawn arc. Let the point of intersection be S.
Step 3: To complete the parallelogram BEST, join E and T to S.