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Factor out x^2+15x-36=0

User Unleashed
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1 Answer

6 votes

For this case we must solve the following quadratic equation:


x ^ 2 + 15x-36 = 0

The equation cannot be factored.

We find the roots by the following formula:


x = \frac {-b \pm \sqrt {b ^ 2-4 (a) (c)}} {2a}

Where:


a = 1\\b = 15\\c = -36

Substituting the values:


x = \frac {-15 \pm \sqrt {15 ^ 2-4 (1) (- 36)}} {2 (1)}\\x = \frac {-15 \pm \sqrt {225 + 144}} {2}\\x = \frac {-15 \pm \sqrt {369}} {2}\\x = \frac {-15 \pm \sqrt {3 ^ 2 * 41}} {2}\\x = \frac {-15 \pm3 \sqrt {41}} {2}

We have two roots:


x_ {1} = \frac {-15 + 3 \sqrt {41}} {2}\\x_ {2} = \frac {-15-3 \sqrt {41}} {2}

Answer:


x_ {1} = \frac {-15 + 3 \sqrt {41}} {2}\\x_ {2} = \frac {-15-3 \sqrt {41}} {2}

User Jeprubio
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