130 likes | 259 Views
January 9 Ms. Wu says … follow the instructions below!. (-4, 12) (10, 6) 34. a. 2 = m + b; 12 = -4m + b b. m = -2, b = 4 c. y = -2x + 4 35. L = 4.5 ft; w = 2.5 ft. Find your new seat . Get out HW 3.2 (don’t have to tear out). Get started on the warm up quietly .
E N D
January 9Ms. Wu says … follow the instructions below! • (-4, 12) • (10, 6) • 34. a. 2 = m + b; 12 = -4m + b • b. m = -2, b = 4 • c. y = -2x + 4 • 35. L = 4.5 ft; w = 2.5 ft. Find your new seat. Get out HW 3.2 (don’t have to tear out). Get started on the warm up quietly. Grade HW 3.2. _______________________________________________ (-3, 29) (5, 7) (-2, 2) (4, 5) (-15, -62) (5, 3) 23. The two equations should be subtracted rather than added; 6x – 8; x = 4/3
New stuff for 2nd semester: • Warm ups • Will not be turned in; grade in class; 10% final grade; points deducted for talking/not doing it/being off-task • Quicky quizzes • Every class period; worth 5 – 10 pts; drop 2 lowest scores; if absent, counts as dropped score • Late homework • Name on door for a week; if not crossed off, mandatory tutorials (call home) • Homework quizzes • Worth 10 pts.; can use homework; cannot drop or make up; if absent, grade homework as quiz
The Elimination Method, pt. 2 Ex1: 3x – 4y = 14 2x + 2y = 21
The Elimination Method, pt. 2 Ex 2: 5x – 6y = 12 3x – 5y = 24
The Elimination Method Process: • Pick the variable you want to eliminate. • Multiply one, or both, equations by a value to make sure the coefficients of the chosen variable are the same (for subtraction) or opposite (for addition). • Subtract/Add and Solve the resulting equation. • Go back to one of the original equations and solve for the other variable.
Group Activity • Study the following Linear Inequalities and determine at least 5 different points (x, y) that make each inequality true. • Plot the points on the board. You cannot plot the same point as another group! • What do you notice about the points that make each linear inequality true? • x ≤ 4 B) y > -2 • C) y < ½ x – 2 D) 2x – y ≥ 4
Graphs from the activity. A B C D
Steps to Graphing • Graph the boundary line • Determine if the boundary is inclusive (solid line) or exclusive (dotted/dashed line) • Test a point and shade the appropriate half plane.
Graphing Linear Inequalities The graphs consist of 1) Boundary Line (graph of corresponding equation) ---- for exclusive ___for inclusive 2) Half-Plane (shaded to indicate included points) Half-Plane: The points on a plane that fall on one side of a boundary line.
Sample Problems • Determine if (4, 5) is a point that satisfies 4x + 2y < 12 • Write inequalities that describes the graphs below.
SIGMA #3 • 10 pt class work grade • 30 minutes, calculators allowed
Quicky Quiz • 5 minutes • Worth 5 points • No notes allowed
HW 3.3 • Pgs 454 – 455: 5, 7, 11, 13, 21, 23, 27, 31, 33, 37