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3 years ago

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Percy solved the equation x2 + 7x + 12 = 12. His work is shown below. Is Percy correct? Explain. 1. (x + 3)(x + 4) = 12 2. x + 3

= 12 or x + 4 = 12 3. x = 9 or x = 8

2 answers:

nevsk [136]3 years ago

8 0

Sample Response: Percy is not correct because he applied the zero product property to a factored expression that was not equal to 0. He should have subtracted 12 from both sides to get x2 + 7x = 0 before factoring. The correct solutions are 0 and -7.

RoseWind [281]3 years ago

4 0

Percy is not correct because he applied the zero product property to a factored expression that was not equal to 0. He should have subtracted 12 from both sides to get x2 + 7x<span> = 0 before factoring. The correct solutions are 0 and -7.</span>

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Step-by-step explanation:

For the first equation, let's use $\frac{-a}{b} =\frac{a}{-b} =-\frac{a}{b}$ to right a new fraction.

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Step 2- Simplify the complex fraction(LCD or Least Common Denominator).

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An alternative form for this fraction is $-3\frac{3}{4} or -3.75$ .

For the second equation..

Step 1- Convert the mixed number to an improper fraction.

$\frac{6\frac{3}{9} }{\frac{11}{5} } = \frac{\frac{57}{9} }{\frac{11}{5} }$

Step 2- Simplify the complex fraction.

$\frac{\frac{57}{9} }{\frac{11}{5} } = \frac{95}{33}$

An alternative form for this fraction is $2\frac{29}{33} or 2.87$ .

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Step 1- Simplify the complex fraction(LCD).

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Write the fraction as a division.

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To divide a fraction, multiply by the reciprocal of that fraction.

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Reduce the fraction with 3.

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Convert the mixed number to an improper fraction.

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Reduce the fraction with -1, this eliminates the negative sign.

Simplify the complex fraction.

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Multiply the numbers.

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