SME
Grade 9 Math

Solving quadratic equations: factoring, square roots, completing the square and the quadratic formula

The main lesson, then each kind of problem it solves.

Solving quadratic equations: factoring, square roots, completing the square and the quadratic formula

Main lesson
Solve by square roots
Use this for “(x − 3)² = 25” or “2(x − 1)² = 18” (a = 1 when there is no number in front).
Complete the square
Use this for “Solve x² + 6x − 7 = 0 by completing the square.”
Quadratic inequality
Use this for “Solve x² − 2x − 8 < 0” or “x² − x − 6 ≥ 0.”
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