Page 168 - ICSE Math 7

3. Are the following pairs of angles complementary?
(a) 20° and 60° (b) 15° and 75° (c) 52°1′ and 37°59′
 2   1 
(d) (x + 74°) and (16° – x) (e)  3 of aright angle and  3 of aright angle
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
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4. Two complementary angles are in the ratio 4 : 5. Find the angles.
5. Three angles which add to 180° are in the ratio 2 : 3 : 4. Find the angles.
6. 20% of an angle is the complement of 74°. Find the angle.
7. In which of the following figures are ∠PQR and ∠PQS adjacent angles?

P R
P S

(a) S (b) (c)

Q R Q S P Q R

8. For the adjoining figure, find the value of:
(a) x S

(b) ∠PQS
x + 63° x + 27°
(c) ∠SQR
P Q R

9. The sum of two adjacent angles is 95°. If one of them measures 15° less than the other, find the
angles.

C
10. In the adjoining figure, ∠ABC and ∠CBD form a linear pair. Find the
value of x. 2x x
A B D

85°
11. Find the values of x and y from the adjoining figure. y + 60° 120° – x

x + 60°
12. Find the value of x for each of the following figures.

x 40°
80° 30°
(a) 125° x 40° (b) 95° 100° (c) x 3x 2x
80°

Transversal p

Transversal is a line which intersects two or more lines at distinct points. 2 1
In the adjoining figure, line p is a transversal for lines q and r. When a 3 4 q
transversal cuts two lines, eight angles are formed as shown in the figure.
These angles can be classified as follows. 6 5 r
7 8

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