Solve the Inequality for x x^2+14x-14>9x

$x^{2} + 14 x - 14 > 9 x$

Move all terms containing $x$ to the left side of the inequality.

Subtract $9 x$ from both sides of the inequality.

$x^{2} + 14 x - 14 - 9 x > 0$

Subtract $9 x$ from $14 x$ .

$x^{2} + 5 x - 14 > 0$

Convert the inequality to an equation.

$x^{2} + 5 x - 14 = 0$

Factor $x^{2} + 5 x - 14$ using the AC method.

Consider the form $x^{2} + b x + c$ . Find a pair of integers whose product is $c$ and whose sum is $b$ . In this case, whose product is $- 14$ and whose sum is $5$ .

$- 2, 7$

Write the factored form using these integers.

$(x - 2) (x + 7) = 0$

If any individual factor on the left side of the equation is equal to $0$ , the entire expression will be equal to $0$ .

$x - 2 = 0$

$x + 7 = 0$

Set $x - 2$ equal to $0$ and solve for $x$ .

Set $x - 2$ equal to $0$ .

$x - 2 = 0$

Add $2$ to both sides of the equation.

$x = 2$

Set $x + 7$ equal to $0$ and solve for $x$ .

Set $x + 7$ equal to $0$ .

$x + 7 = 0$

Subtract $7$ from both sides of the equation.

$x = - 7$

The final solution is all the values that make $(x - 2) (x + 7) = 0$ true.

$x = 2, - 7$

Use each root to create test intervals.

$x < - 7$

$- 7 < x < 2$

$x > 2$

Choose a test value from each interval and plug this value into the original inequality to determine which intervals satisfy the inequality.

Test a value on the interval $x < - 7$ to see if it makes the inequality true.

Choose a value on the interval $x < - 7$ and see if this value makes the original inequality true.

$x = - 10$

Replace $x$ with $- 10$ in the original inequality.

${(- 10)}^{2} + 14 (- 10) - 14 > 9 (- 10)$

The left side $- 54$ is greater than the right side $- 90$ , which means that the given statement is always true.

True

Test a value on the interval $- 7 < x < 2$ to see if it makes the inequality true.

Choose a value on the interval $- 7 < x < 2$ and see if this value makes the original inequality true.

$x = 0$

Replace $x$ with $0$ in the original inequality.

${(0)}^{2} + 14 (0) - 14 > 9 (0)$

The left side $- 14$ is not greater than the right side $0$ , which means that the given statement is false.

False

Test a value on the interval $x > 2$ to see if it makes the inequality true.

Choose a value on the interval $x > 2$ and see if this value makes the original inequality true.

$x = 4$

Replace $x$ with $4$ in the original inequality.

${(4)}^{2} + 14 (4) - 14 > 9 (4)$

The left side $58$ is greater than the right side $36$ , which means that the given statement is always true.

True

Compare the intervals to determine which ones satisfy the original inequality.

$x < - 7$ True

$- 7 < x < 2$ False

$x > 2$ True

$x < - 7$ True

$- 7 < x < 2$ False

$x > 2$ True

The solution consists of all of the true intervals.

$x < - 7$ or $x > 2$

The result can be shown in multiple forms.

Inequality Form:

$x < - 7 or x > 2$

Interval Notation:

$(- \infty, - 7) \cup (2, \infty)$

Solve the Inequality for x x^2+14x-14>9x

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