Bell Work Jackson opened a bank account and is saving for a new pair of shoes. The table below shows his progress. How much does Jackson save each week? ___________________ How much did he put in the bank when he opened his account? ___________ Write an equation to represent this data. ______________ (23.F.4) Weeks 3 5 8 9 Savings ($) 56 80 116 128 Would you describe the relationship between the x and y values in the table as linear or non-linear? How do you know? Explain your answer. x 1 2 3 4 y 9 16

7.6 Equations in y = mx Form 7.7 Slope-Intercept Form

Definition - Intercepts The x-intercept of a straight line is the x-coordinate of the point where the graph crosses the x-axis. The y-intercept of a straight line is the y-coordinate of the point where the graph crosses the y-axis. y y-intercept x x-intercept BACK

What is the y-intercept? -4 1 -3 -2 2 3 -1 5 4 -5 What is the y-intercept? y-intercept = 3 y-intercept = -4 y-intercept = -3 y-intercept = 5 y-intercept = 0

Slope-Intercept Form BACK

Slope is Rise over Run. The Denominator The Numerator Tells you to “rise” up or down Positive = Up Negative = Down The Denominator Tells you how far to “run” left or right Positive = Right Negative = Left. BACK

BACK

Finding the slope and y-intercept State the slope and y-intercept of: y = 3x + 2 BACK

y = 3x + 2 Y Slope = 3/1 y-intercept= 2 X Up 3 and Right 1 BACK

y = -2x + 3 Y Slope = -2/1 y-intercept= 3 X Down 2 and Right 1 BACK

y = 3x -2 Y You try this one X BACK

y = 3x -2 Y X BACK

Slope = -1/2 y-intercept= 2 Y X Down 1 Right 2 BACK

Y X BACK

4 Types of Slope for a Line 1 - Positive Slope Bottom left to top right y = +mx + b 2 - Negative Slope Top left to bottom right y = -mx + b

4 Types of Slope for a Line 3 - Zero Slope Horizontal Line y = # 4 - Undefined Slope Vertical Line x = #

Homework Pg. 511 ALL Classes: 2 – 10 even Pg. 519 HC: 1-15 all RC: 1-11, 14, 15