Lesson 5 Summary
Zero Product Property
If ab = 0, then a = 0 or b= 0 or a = b = 0
When solving for the variable in a quadratic equation, rewrite the equation as a factored quadratic set equal to zero. Using the zero product property, you know that if one factor is equal to zero, then the product of all factors is equal to zero.
Going one step further, when you have set each binomial factor equal to zero and solved for the variable, all of the possible solutions for the equation have been found. Given the context, some solutions may not be viable, so be sure to determine if each possible solution is appropriate for the problem.
x2 + 8x + 15 = 0
7r2 - 14r = - 7
x3 - 81x = 0
Lesson 5 Problem Set Sample Solutions
Solve the following equations.
1. x2 - 11x + 19 = -5
2. 7x2 + 2x = 0
3. b2 + 5b - 35 = 3b
4. 6r2 - 12r = -6
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