8­6 Solving x^2+bx+c day 3.notebook
January 25, 2015
8­6 Solving x2 +bx +c =0
Quadratic Equation standard form:
Goals:
ax2+bx+c = 0, where a ≠ 0
1. Factor trinomials of the form x2 +bx +c.
2. Solve equations of the form x2 +bx +c = 0 The name Quadratic comes from "quad" meaning square, because the variable gets squared (like x2).
Some equations in this form can be solved by factoring and then using the Zero Product Property.
To solve an equation:
Solve: z2 ­3z =70
Check your solutions.
1. Make sure the equation is = 0
2. Factor
2. Set each factor = 0
4. Solve each factor for the variable.
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8­6 Solving x^2+bx+c day 3.notebook
Solve: x2 +3x ­18 = 0
January 25, 2015
Check your solutions.
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The height of a parallelogram is 18 centimeters less than its base. If the area if 175 square centimeters, what is its height?
8­6 day 3 Assignment:
Page 507: 20­32 all
Read Section 8­7 A = b x h
7cm
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8­6 Solving x^2+bx+c day 3.notebook
January 25, 2015
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