Linear Functions and Graph Analysis Study Notes

Class Announcements and Schedule

  • Complete the three graphs and remaining packet pages before working on the review guide.

  • The test is scheduled for Thursday of next week.

  • Delta bound practice and delta knot are posted online for additional review.

Linear Savings Model Properties

  • Initial Value (Y-intercept): The starting value is $4.07\$4.07 or $4.75\$4.75, providing the ordered pair (0,4.75)(0, 4.75).

  • Rate of Change: Adds $1.25\$1.25 for each week (xx).

  • Model Equation: Written as f(x)=1.25x+4.75f(x) = 1.25x + 4.75.

  • Variable Classification: Continuous, as partial dollar amounts such as $0.50\$0.50 are valid.

  • End Behavior: As xx \rightarrow \infty (moving right), f(x)f(x) \rightarrow \infty (moving upward).

  • Intervals: Positive when x > 0 and never negative.

  • Domain and Range: Domain starts at 00 and extends infinitely or to an upper bound of 70007000 ([0,7000][0, 7000] or [0,)[0, \infty)). Range starts at $4.75\$4.75 up to 70007000 ([4.75,7000][4.75, 7000]).

Continuous Tank Filling Model

  • Fill Rate: Water fills at a rate of 20gallons per minute20\,\text{gallons per minute}.

  • Sub-unit Calculation: At 30seconds30\,\text{seconds} (0.5minutes0.5\,\text{minutes}), the volume is 10gallons10\,\text{gallons}.

  • Variable Classification: Continuous, as time measured in decimal seconds (such as 28seconds28\,\text{seconds}) yields continuous gallon values.

Questions & Discussion

  • Question on Table Setup: A student asked Mister Lumpkin how to construct the table values from copied notes.

  • Response: Start with x=0x = 0 at $4.75\$4.75, then increment xx by 11 each week while adding $1.25\$1.25 to the total.

  • Question on Negative Values: A student inquired why negative values are not represented on the graph.

  • Response: A negative number of days cannot exist in this scenario, so the y-intercept (0,4.75)(0, 4.75) serves as the starting point.

  • Discussion on Past Teacher: Students discussed Miss Vickery, debating whether she retired or was fired during the previous year.

  • Classroom Remarks: Brief exchanges occurred involving Lacey regarding Obamotration and Brian.