Page 330 - C:\Users\azizu\Documents\Flip PDF Professional\Matematics-Form-1-1\

(b) A B Self Practice 9.3a 2. (a)
H C 1. All sides have the same length;
opposite sides are parallel;
G D
diagonals are perpendicular
F E bisectors of each other. (b)
Octagon ABCDEFGH
(c) B C 2. Rectangle Parallelogram
A D Opposite sides Opposite sides
J E are of the same are of the same 3. x = 164°, y = 74°
I F length and length and 4. x = 34°, y = 66°
H G parallel. parallel.
Decagon ABCDEFGHIJ All of its Opposite Let’s Practise
interior angles angles are
Mastery 9.1 1. (a) 3
are 90°. equal. (b) 3
1. (a) True (b) True Diagonals Diagonals are (c) 7
2. A B are of equal bisectors of (d) 3
length and are each other. 2. (a) Rectangle, rhombus
H C bisectors of (b) Scalene triangle
each other. (c) Square, rhombus
G D It has two axes It does not (d) Rectangle, square
of symmetry. have any axes 3. (a) 85°
F E of symmetry. (b) 24°
Name of polygon: octagon (c) 50.5°
Number of diagonals: 20 Self Practice 9.3b (d) 15°
1. 121° 4. x = 53°, y = 53°
Self Practice 9.2a
2. x = 84°, y = 90° 5. x = 15°, y = 60°
1. (a) Obtuse-angled triangle; or
scalene triangle Self Practice 9.3c 6. The largest number in the ratio
(b) Equilateral triangle 1. x = 152°, y = 121° is 6; 120°
(c) Right-angled triangle 2. x = 132°, y = 138° 7. 75°
(d) Acute-angled triangle; or 8. x = 112°, y = 44°
scalene triangle Self Practice 9.3d 9. x = 30°, y = 74°
1. x = 72°, y = 108°
Self Practice 9.2b 10. x = 56°, y = 62°
2. x = 30°, y = 72°
1. (a) 35° (b) 47° 11. x = 53°, y = 127°
(c) 27° (d) 42° Mastery 9.3
2. (a) 123° (b) 54° 1. Similarities: Chapter 10 Perimeter and Area
(c) 82° (d) 76°
• Opposite sides are of equal Self Practice 10.1a
Self Practice 9.2c length and parallel.
• Opposite angles are equal. 1. (a) 74 cm
1. x = 56°, y = 32° (b) 71 cm
2. x = 60°, y = 89° Differences: (c) 13 cm
Parallelogram
Mastery 9.2 • Opposite sides are of equal Self Practice 10.1b
1. (a) 1 (b) 3 length. The estimated answers depend on
(c) 1 (d) 1 • Diagonals are bisectors of the students.
2. (a) Equilateral triangle each other.
(b) Isosceles triangle • It does not have any axes of 1. (a) Estimation: 10 cm
(c) Obtuse-angled triangle; or symmetry. Perimeter: 9.9 cm
scalene triangle Rhombus The difference between the
(d) Right-angled triangle • All sides have the same length. estimated value and the actual
3. x = 56°, y = 118° • Diagonals are perpendicular value is small, therefore the
bisectors of each other. estimated value is accurate.
4. x = 108°, y = 144°
• It has 2 axes of symmetry.
5. x = 160°, y = 62°

319
Answers

14 Ans Math F1.indd 319 11/10/16 12:23 PM