Example 3
Completion requirements
Example 3
Solve 
by factoring.
One side of the equation is 0, so factor the quadratic expression. Begin by taking out the GCF.
Factor 
as a difference of squares.
and 
, so factors to 
.
Determine what values of the variable make each factor equal to zero.
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The solutions to are 4 and −4. Verify the solutions by substituting them into the original equation.
For a = 4,
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Left side
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Right side
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0
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LS = RS
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The two sides are equal, so 4 is a solution.
For a = -4,
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Left side
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Right side
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0
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LS = RS
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The two sides are equal, so -4 is also a solution.