SWBAT determine if a graph is a function, and the domain and range On white board:

Function Definition There exists only ONE ‘y’ value for a single ‘x’ – Two different ‘X’ can have the same ‘Y’ Value Functions:Not Function X: { 1, 2, 3, 4, 5}X: { 1, 2, 1, 3, 4} Y: { 3, 2, 1, 3, 8}Y: { 2, 3, 7, 8, 6}

Functions as a Dance Invite Boys are XGirls are Y Multiple boys can ask a girl to a dance: Jake, Brian, & Steve invited Megan to homecoming:  Function A boy cannot ask multiple girls to the dance (the girls will talk and none will go with him) Tom asks Laura, Stephanie, & Kelly  Not a function

Function of a graph Vertical Line Test!!!!!! – Imagine vertical lines pass through the grid. – If lines touch graph in two places, it fails and is not a function.

Homework PG 136 4A and pg 139 4B #1-2 All

SWBAT use interval notation to describe the domain and range of functions and non functions Solve each Variable: x + 2y - 3z + 4w = 12 2x + 2y - 2z + 3w = y + z + 0 = -1 x - y + z - 2w = -4

Interval Notation [ or ] includes a point just like a filled in dot on a graph ( or ) is used to describe up to that point just like an open dot on a graph – Also used to describe + or - negative infinity Because we never “Get To” infinity -3 < x < 9 gets written as (-3, 9)

Domain Function: X: { 1, 3, 6, 9, 10} Y: { -1, -4, -4, -10, -13} Possible ‘X’ values of a function – If specific points, list exact numbers. Domain: { 1, 3, 6, 9, 10} – If continues, give a range of values Ex: [-1, 10)

Range: Function: X: { 1, 3, 6, 9, 10} Y: { -1, -4, -4, -10, -13} Possible Y values from a graph or function If specific points, list exact numbers. – Range: { -1, -4, -10, -13} If continuous graph, give interval Range: (3, 19]