Precalculus Examples

$5 x^{2} + 40 x + 5 y^{2} = 0$

Step 1

Find the x-intercepts.

Tap for more steps...

Step 1.1

To find the x-intercept(s), substitute in $0$ for $y$ and solve for $x$ .

$5 x^{2} + 40 x + 5 {(0)}^{2} = 0$

Step 1.2

Solve the equation.

Tap for more steps...

Step 1.2.1

Simplify $5 x^{2} + 40 x + 5 {(0)}^{2}$ .

Tap for more steps...

Step 1.2.1.1

Simplify each term.

Tap for more steps...

Step 1.2.1.1.1

Raising $0$ to any positive power yields $0$ .

$5 x^{2} + 40 x + 5 \cdot 0 = 0$

Step 1.2.1.1.2

Multiply $5$ by $0$ .

$5 x^{2} + 40 x + 0 = 0$

Step 1.2.1.2

Add $5 x^{2} + 40 x$ and $0$ .

$5 x^{2} + 40 x = 0$

Step 1.2.2

Factor $5 x$ out of $5 x^{2} + 40 x$ .

Tap for more steps...

Step 1.2.2.1

Factor $5 x$ out of $5 x^{2}$ .

$5 x (x) + 40 x = 0$

Step 1.2.2.2

Factor $5 x$ out of $40 x$ .

$5 x (x) + 5 x (8) = 0$

Step 1.2.2.3

Factor $5 x$ out of $5 x (x) + 5 x (8)$ .

$5 x (x + 8) = 0$

Step 1.2.3

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

$x = 0$

$x + 8 = 0$

Step 1.2.4

Set $x$ equal to $0$ .

$x = 0$

Step 1.2.5

Set $x + 8$ equal to $0$ and solve for $x$ .

Tap for more steps...

Step 1.2.5.1

Set $x + 8$ equal to $0$ .

$x + 8 = 0$

Step 1.2.5.2

Subtract $8$ from both sides of the equation.

$x = - 8$

Step 1.2.6

The final solution is all the values that make $5 x (x + 8) = 0$ true.

$x = 0, - 8$

Step 1.3

x-intercept(s) in point form.

x-intercept(s): $(0, 0), (- 8, 0)$

Step 2

Find the y-intercepts.

Tap for more steps...

Step 2.1

To find the y-intercept(s), substitute in $0$ for $x$ and solve for $y$ .

$5 {(0)}^{2} + 40 (0) + 5 y^{2} = 0$

Step 2.2

Solve the equation.

Tap for more steps...

Step 2.2.1

Simplify $5 {(0)}^{2} + 40 (0) + 5 y^{2}$ .

Tap for more steps...

Step 2.2.1.1

Simplify each term.

Tap for more steps...

Step 2.2.1.1.1

Raising $0$ to any positive power yields $0$ .

$5 \cdot 0 + 40 (0) + 5 y^{2} = 0$

Step 2.2.1.1.2

Multiply $5$ by $0$ .

$0 + 40 (0) + 5 y^{2} = 0$

Step 2.2.1.1.3

Multiply $40$ by $0$ .

$0 + 0 + 5 y^{2} = 0$

Step 2.2.1.2

Combine the opposite terms in $0 + 0 + 5 y^{2}$ .

Tap for more steps...

Step 2.2.1.2.1

Add $0$ and $0$ .

$0 + 5 y^{2} = 0$

Step 2.2.1.2.2

Add $0$ and $5 y^{2}$ .

$5 y^{2} = 0$

Step 2.2.2

Divide each term in $5 y^{2} = 0$ by $5$ and simplify.

Tap for more steps...

Step 2.2.2.1

Divide each term in $5 y^{2} = 0$ by $5$ .

$\frac{5 y^{2}}{5} = \frac{0}{5}$

Step 2.2.2.2

Simplify the left side.

Tap for more steps...

Step 2.2.2.2.1

Cancel the common factor of $5$ .

Tap for more steps...

Step 2.2.2.2.1.1

Cancel the common factor.

$\frac{5 y^{2}}{5} = \frac{0}{5}$

Step 2.2.2.2.1.2

Divide $y^{2}$ by $1$ .

$y^{2} = \frac{0}{5}$

Step 2.2.2.3

Simplify the right side.

Tap for more steps...

Step 2.2.2.3.1

Divide $0$ by $5$ .

$y^{2} = 0$

Step 2.2.3

Take the specified root of both sides of the equation to eliminate the exponent on the left side.

$y = \pm \sqrt{0}$

Step 2.2.4

Simplify $\pm \sqrt{0}$ .

Tap for more steps...

Step 2.2.4.1

Rewrite $0$ as $0^{2}$ .

$y = \pm \sqrt{0^{2}}$

Step 2.2.4.2

Pull terms out from under the radical, assuming positive real numbers.

$y = \pm 0$

Step 2.2.4.3

Plus or minus $0$ is $0$ .

$y = 0$

Step 2.3

y-intercept(s) in point form.

y-intercept(s): $(0, 0)$

Step 3

List the intersections.

x-intercept(s): $(0, 0), (- 8, 0)$

y-intercept(s): $(0, 0)$

Step 4