Page 251 - Start Up Mathematics_8 (Non CCE)

Thinking Skills

1. Construct a trapezium WIND in which WI = 8.5 cm, IN = 5 cm, ND = 4.5 cm, –I = 60º and WI || ND.
2. Construct a trapezium SOME in which SO || ME, SO = 5.5 cm, OM = 4 cm, SE = 5.5 cm and –O = 60º.
3. Construct a parallelogram MARK in which MA = 5 cm, –A = 110º, –RMA = 35º.
4. Construct a rectangle DATE in which DA = 4 cm and the diagonal DT = 5 cm.
5. Construct a rectangle CARE in which diagonal AE = 5.6 cm and the diagonals CR and AE intersect at
O such that –AOR = 45º.

Some NCERT Textbook Questions
1. Construct the following quadrilaterals.
(i) Quadrilateral ABCD. (ii) Rhombus BEST
AB = 4.5 cm BE = 4.5 cm
BC = 5.5 cm ET = 6 cm
CD = 4 cm
AD = 6 cm
AC = 7 cm
2. Construct the following quadrilaterals.
(i) Quadrilateral LIFT (ii) Rhombus BEND
LI = 4 cm BN = 5.6 cm
IF = 3 cm DE = 6.5 cm
TL = 2.5 cm
LF = 4.5 cm
IT = 4 cm
3. Construct the following quadrilaterals.
Construct a quadrilateral TRUE:
TR = 3.5 cm
RU = 3 cm
UE = 4 cm
∠R = 75°
∠U = 120°

Exemplar Problems

1. A parallelogram PQRS is constructed with sides QR = 6 cm, PQ = 4 cm and –PQR = 90°. Then PQRS is:
(a) square (b) rectangle (c) rhombus (d) trapezium
2. To construct a unique rectangle, minimum number of measurements required is:
(a) 4 (b) 3 (c) 2 (d) 1
3. A quadrilateral can be constructed uniquely if its three sides and ___________ angles are given.
4. A quadrilateral can have all four angles as obtuse. (True/False)
5. A rhombus can be constructed uniquely if both diagonals are given. (True/False)
6. Construct a trapezium ABCD in which AB || DC, –A = 105°, AD = 3 cm, AB = 4 cm and CD = 8 cm.
7. Construct a parallelogram POUR in which, PO = 5.5 cm, OU = 7.2 cm and –O = 70°.
8. Construct a quadrilateral BEAR in which BE = 6 cm, EA = 7 cm, RB = RE = 5 cm and BA = 9 cm.
Measure its fourth side.
9. Construct a rectangle whose one side is 3 cm and a diagonal equal to 5 cm.
10. Construct a parallelogram when one of its side is 4 cm and its two diagonals are 5.6 cm and 7 cm. Measure
the other side.
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