Page 57 - 01-Yr5_Front cover-ccp.indd

• More slab patterns • • • • • • Number machines • • • • •
rn Use this number machine to help you with this page
~=I•I-l:f01EJ--
PAGE 33
rn

rn Check that 18 is correct by substituting it for n
in the left side of the machine.
~ Find the answers to these. You could record like this:
~ Complete this table to show your results so for.
n~~..!2....l2n+9=45J~/ 2n =36 l-'1..~
A represents the number of squores on each arm.
C represents the total number of squares in the crosses
[[) Without drawing diagrams, decide the next three entries for the table.
El Explain in words the rule connecting both columns of the table.
fi§] Decide what to write INPUT D OUTPUT
in the operations box. A c
[[j Complete this formula so that it is true for every example. C =
rn Drow the 8th and 10th crosses for the pattern.
Check that your answers to [ijJ, I]] and~ are true for these.
CHALLENGE
rn

Check that 18 is correct by
substitution.

~ cg] x7 -12 +12 +7

~ 7n - 12 = 65
A c INPUT x4+ !:> OUTPUT n~~ ~ 7n = 77 ~ OJ]
A c
1 5 x2 +5 -5 +2
~ 2n + 5 = q1
2 q [ID n~~ ~ 2n = q2 ~ ~
xl 1 -25 +25 +11
3 13 C = 4A + 1
n~ ITGJ ~I 11 n - 25 = 85 ~ llln= 1101 ~ [@]
4 17
xq +7 -7 +q
5 21
n~ [§IL] ~ I qn - 1 = a8 ~ I qn = a1 ~ [I]
Practical: drawing 8th and 10th
6 25
crosses. Check when A = 8, C = 33 x6 +8 -8 +6
7 2q and when A= 10, C = 41. ~ w
n ~[§_ii] ~ 6n + 8 = 62 ~ 6n = 54 I
8 33
x3 +10 -10 +3
Challenge
n~~~I 3n + 10 = 64 I ~ 3n = 54 ~ [Ji]
The number of rails is four times
Multiply the number of squares on one fewer than the number of 00
each arm by 4, then add 1 . posts.
R = 4(P - 1) or P = t R + 1 Check answers by substitution.