Function Tables

Complete a function table Function Rule + 4 Output

Complete the table…… Input (x) =2, 5, 8 Function Rule = What you DO to x? X - 2 Output (y)=0, 3,

What’s the output? X

What’s the output?

Find the function rule X 3 Keep in mind – the rule MUST be the same for EVERY input.

Find the function rule What do you do to x (the input) to get to y (the output)? ? ÷ ? -12 ÷ 4 Function Rule is x ÷ 4

“Combination” rules Rules that have x or ÷ AND + or - Input(x)Output ( ? ) Basic + or – won’t work Basic x or ÷ won’t work SO Start with multiplying by 2 then adding or subtracting until you reach the output. Do this for the second output – does it work? X OK NOT 23

“Combination” rules Rules that have x or ÷ AND + or - Input(x)Output ( ? ) If 2 doesn’t work, then try multiplying by 3 and then adding or subtracting until you reach the output. X Try the same rule for the following outputs. If it works for ALL the outputs, then it’s the rule! If not, then try 4, 5, 6 and so on until you find one that works for all the outputs. X The rule is 3x + 2

Find the function rule Input (x)Output ( ? ) x - 1

Real world situation Use a variable to represent the input – called “Defining the variable” Set up a table with the 2 things you are comparing hours (x )Dollars 1$70 2$140 X ? So the function rule is 70X

Sister (s)Ricardo S? Rule is S + 8 Sister (s)Ricardo