Finding the Rule Algebraic patterns

Finding the rule – guess & check x y 1 7 2 14 3 21 4 28 5 35 X 7

Finding the recursive rule A recursive rule is one which can be applied over and over again to its own output Eg. 124, 127, 130, 133, 136 (recursive rule is + 3) Eg. 29, 19, 9, -1, -11, -21 (recursive rule is -10) x y 15 30 16 31 17 32 18 33 19 34 Recursive rule is + 1

Finding the input/output rule x y 15 30 16 31 17 32 18 33 19 34 y = x + 15

Finding the input/output rule (continued) x y 1 9 2 11 3 13 4 15 5 17 What is the recursive rule? + 2 This recursive rule gives us a clue to the input/output rule. y = mx + c m = recursive rule y = 2x + c Therefore y = 2x + 7

Finding the input/output rule Try your own x y 1 6 2 11 3 16 4 21 5 26 First, find the recursive rule. The recursive rule tells us the multiplier (m). y = mx + c

Try another one x y 1 10 2 18 3 26 4 34 5 42

Go the other way x y 1 ? 2 3 4 5 10 40 100 y = 10x + 5