PREVIOUSLY YOU LEARNED THAT THE QUADRATIC FORMULA CAN SOLVE ANY QUADRATIC EQUATION AX 2 + BX + C = 0 IF A ≠ 0. BUT WHAT IF THE EQUATION IS NOT IN STANDARD FORM? WHAT IF TERMS ARE MISSING? IS USING THE QUADRATIC FORMULA ALWAYS THE BEST METHOD? Examine the quadratic equations below with your team. For each equation: Decide which strategy to try first. Zero Product Property (factoring) Completing the Square Quadratic Formula Solve the equation. If your first strategy does not work, use a different strategy. Check your solution(s). Be prepared to share your process with the class. a.x x + 27 = 0 b.4x 2 − 121 = 0 c.(3x + 4)(2x − 1) = 0 d.x = 8x − 4 e.36x = 60x f.20x 2 − 30x = 2x + 45

5.2.5 SOLVING AND APPLYING QUADRATIC EQUATIONS FEBRUARY 2, 2016

OBJECTIVES CO: SWBAT use the Zero Product Property, completing the square, and the Quadratic Formula. LO: SWBAT explain when it is best to use each method.

LEARNING LOG - CHOOSING A STRATEGY TO SOLVE QUADRATIC EQUATIONS Decide when it is best to solve a quadratic by factoring & using the Zero Product Property, completing the square, or when you should go directly to the Quadratic Formula. Zero Product Property Equation looks factorable Equation has “nice” coefficients Equation is already factored and equal to zero Completing the Square Equation is not easily factorable Works for any quadratic equation, but is much easier if: coefficient of x 2 is 1 x is an even number Quadratic Formula Works for any quadratic equation rewritten in standard form Good for decimal or fractional coefficients Good for large ugly numbers