Solve for x x^2-7x>0

$x^{2} - 7 x > 0$

Step 1

Convert the inequality to an equation.

$x^{2} - 7 x = 0$

Step 2

Factor $x$ out of $x^{2} - 7 x$ .

Factor $x$ out of $x^{2}$ .

$x \cdot x - 7 x = 0$

Factor $x$ out of $- 7 x$ .

$x \cdot x + x \cdot - 7 = 0$

Factor $x$ out of $x \cdot x + x \cdot - 7$ .

$x (x - 7) = 0$

Step 3

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

$x = 0$

$x - 7 = 0$

Step 4

Set $x$ equal to $0$ .

$x = 0$

Step 5

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

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

$x - 7 = 0$

Add $7$ to both sides of the equation.

$x = 7$

Step 6

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

$x = 0, 7$

Step 7

Use each root to create test intervals.

$x < 0$

$0 < x < 7$

$x > 7$

Step 8

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 $x < 0$ to see if it makes the inequality true.

Choose a value on the interval $x < 0$ and see if this value makes the original inequality true.

$x = - 2$

Replace $x$ with $- 2$ in the original inequality.

${(- 2)}^{2} - 7 \cdot - 2 > 0$

The left side $18$ is greater than the right side $0$ , which means that the given statement is always true.

True

Test a value on the interval $0 < x < 7$ to see if it makes the inequality true.

Choose a value on the interval $0 < x < 7$ and see if this value makes the original inequality true.

$x = 4$

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

${(4)}^{2} - 7 \cdot 4 > 0$

The left side $- 12$ is not greater than the right side $0$ , which means that the given statement is false.

False

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.

${(10)}^{2} - 7 \cdot 10 > 0$

The left side $30$ is greater than the right side $0$ , which means that the given statement is always true.

True

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

$x < 0$ True

$0 < x < 7$ False

$x > 7$ True

$x < 0$ True

$0 < x < 7$ False

$x > 7$ True

Step 9

The solution consists of all of the true intervals.

$x < 0$ or $x > 7$

Step 10

The result can be shown in multiple forms.

Inequality Form:

$x < 0 or x > 7$

Interval Notation:

$(- \infty, 0) \cup (7, \infty)$

Step 11

Solve for x x^2-7x>0

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