SME
Grade 9 Math
Systems by elimination, and systems of linear inequalities
The main lesson, then each kind of problem it solves.
Systems by elimination, and systems of linear inequalities
Main lesson
Solve a system by elimination
Use this for “Solve 3x + 2y = 16 and 5x − 4y = 12 by elimination.”
A budget and a count
Use this for “Adult tickets are $10 and student tickets $6. Spend at most $144 on at most 20 tickets.”
System of inequalities in standard form
Use this for “Graph x − 2y < 2 and 2x + y ≤ 4 and test (−6, 2).”
A box of points: a ≤ x ≤ b and c ≤ y ≤ d
Use this for “Shade the points with −3 ≤ x ≤ 2 and −1 ≤ y ≤ 4.”
A line and a parabola
Use this for “Solve y = x² − 2x − 3 and y = x + 1.”