4. Similar Triangles
TESTS
(1) Corresponding sides are in proportion (SSS – with ratio a:b)
(2) Two pairs of corresponding sides are in proportion AND the
included angles are equal (SAS – with ratio a:b)
5. Similar Triangles
TESTS
(1) Corresponding sides are in proportion (SSS – with ratio a:b)
(2) Two pairs of corresponding sides are in proportion AND the
included angles are equal (SAS – with ratio a:b)
(3) All three angles are the same as the three angles in the other (AA)
6. Similar Triangles
TESTS
(1) Corresponding sides are in proportion (SSS – with ratio a:b)
(2) Two pairs of corresponding sides are in proportion AND the
included angles are equal (SAS – with ratio a:b)
(3) All three angles are the same as the three angles in the other (AA)
e.g. Find AD
C
21 cm
E
15 cm
A B
D
24 cm
7. Similar Triangles
TESTS
(1) Corresponding sides are in proportion (SSS – with ratio a:b)
(2) Two pairs of corresponding sides are in proportion AND the
included angles are equal (SAS – with ratio a:b)
(3) All three angles are the same as the three angles in the other (AA)
e.g. Find AD
C DAE BAC common A
21 cm
E
15 cm
A B
D
24 cm
8. Similar Triangles
TESTS
(1) Corresponding sides are in proportion (SSS – with ratio a:b)
(2) Two pairs of corresponding sides are in proportion AND the
included angles are equal (SAS – with ratio a:b)
(3) All three angles are the same as the three angles in the other (AA)
e.g. Find AD
C DAE BAC common A
21 cm
E EDA CBA corresponding' s, BC||DE A
15 cm
A B
D
24 cm
9. Similar Triangles
TESTS
(1) Corresponding sides are in proportion (SSS – with ratio a:b)
(2) Two pairs of corresponding sides are in proportion AND the
included angles are equal (SAS – with ratio a:b)
(3) All three angles are the same as the three angles in the other (AA)
e.g. Find AD
C DAE BAC common A
21 cm
E EDA CBA corresponding' s, BC||DE A
15 cm
DAE ||| BAC AA
A B
D
24 cm
11. A A
24 cm 36 cm 15 cm
B C D E
AD AE
ratio of sides in ||| ' s
AB AC
12. A A
24 cm 36 cm 15 cm
B C D E
AD AE
ratio of sides in ||| ' s
AB AC
AD 15
24 36
AD 10cm
13. A A
24 cm 36 cm 15 cm
B C D E
AD AE
ratio of sides in ||| ' s
AB AC
AD 15
24 36
AD 10cm
In similar shapes;
14. A A
24 cm 36 cm 15 cm
B C D E
AD AE
ratio of sides in ||| ' s
AB AC
AD 15
24 36
AD 10cm
In similar shapes;
If sides are in the ratio a : b
15. A A
24 cm 36 cm 15 cm
B C D E
AD AE
ratio of sides in ||| ' s
AB AC
AD 15
24 36
AD 10cm
In similar shapes;
If sides are in the ratio a : b
area is in the ratio a 2 : b 2
16. A A
24 cm 36 cm 15 cm
B C D E
AD AE
ratio of sides in ||| ' s
AB AC
AD 15
24 36
AD 10cm
In similar shapes;
If sides are in the ratio a : b
area is in the ratio a 2 : b 2
volume is in the ratio a 3 : b 3
17. A A
24 cm 36 cm 15 cm
B C D E
AD AE
ratio of sides in ||| ' s
AB AC
AD 15
24 36
AD 10cm
In similar shapes;
Exercise 8H; 2bd, 4ab, 6bc,
If sides are in the ratio a : b
8, 12, 16, 18, 20, 21, 24*
area is in the ratio a 2 : b 2
volume is in the ratio a 3 : b 3