# + + rds + Pythagoras Definition: SURD FORM + + rds + Pythagoras Definition: SURD FORM a b c 0 1 7 Where a, b and c are rational numbers 7 3 9 39 5

5 4 4 4 starter SURDS are 49 1 3 5 6.34812 are not 7 4 3 19

1 6 2 4 5 2 Notes: Reminder: ab = a b and for example:

a/b = /b a Surds KUS objectives BAT simplify Surds in different types of problems Simplify Challenge Draw a line with a length of exactly 5 units

B A Click for a hint: C WB22 Pythagoras reminder B Find length BC and express your answer as an exact simplified value 6 BC2 = 62 + 42 BC = 52 BC = 4 13 BC = 2 13

A 4 C C WB 23 Pythagoras B is (11 , 6) C is ( 1.5, 10) and D is (-2, 3) a) Show that length BC is b) Show that length CD is BC 2 4

19 2 2 42 19 2 BC 2 361 4 16 64 425 BC 2 361 4 4 4

BC 425 4 25 17 4 5 217 B WB 24a C 14

A D 2 B E Write the lengths of AB and DF in the form F  WB 24b find the missing length and give the answer as a simplified surd (all triangles are RATS) E

B A H ? G 8 ? 11 ? J 50 5

F D C 5 6 ? 48 I K 30

L Pythagoras problem: WB 25a What is the exact area of the triangle? 5 5 25 5 Height triangle = Area triangle = 1 2

20 5 20 1 2 100 5 WB 25b Try these (find the area): 26 34 2 Ans: 4 8

Ans: 6 19 15 30 Ans: 7.5 12 Ans: 21 KUS objectives BAT self-assess One thing learned is

One thing to improve is END Practice Ex 1A HWK 1B