Pre-Algebra Examples

$(x^{4} - 10 x^{2} + 31) \div (x^{2} - 5)$

Step 1

Set up the polynomials to be divided. If there is not a term for every exponent, insert one with a value of $0$ .

$x^{2}$

$0 x$

$5$

$x^{4}$

$0 x^{3}$

$10 x^{2}$

$0 x$

$31$

Step 2

Divide the highest order term in the dividend $x^{4}$ by the highest order term in divisor $x^{2}$ .

$x^{2}$

$0 x$

$5$

$x^{4}$

$0 x^{3}$

$10 x^{2}$

$0 x$

$31$

Step 3

Multiply the new quotient term by the divisor.

$x^{2}$

$0 x$

$5$

$x^{4}$

$0 x^{3}$

$10 x^{2}$

$0 x$

$31$

$x^{4}$

$0$

$5 x^{2}$

Step 4

The expression needs to be subtracted from the dividend, so change all the signs in $x^{4} + 0 - 5 x^{2}$

$x^{2}$

$0 x$

$5$

$x^{4}$

$0 x^{3}$

$10 x^{2}$

$0 x$

$31$

$x^{4}$

$0$

$5 x^{2}$

Step 5

After changing the signs, add the last dividend from the multiplied polynomial to find the new dividend.

$x^{2}$

$0 x$

$5$

$x^{4}$

$0 x^{3}$

$10 x^{2}$

$0 x$

$31$

$x^{4}$

$0$

$5 x^{2}$

Step 6

Pull the next term from the original dividend down into the current dividend.

$x^{2}$

$0 x$

$5$

$x^{4}$

$0 x^{3}$

$10 x^{2}$

$0 x$

$31$

$x^{4}$

$0$

$5 x^{2}$

$0 x$

$31$

Step 7

Divide the highest order term in the dividend $- 5 x^{2}$ by the highest order term in divisor $x^{2}$ .

$x^{2}$

$0 x$

$5$

$x^{2}$

$0 x$

$5$

$x^{4}$

$0 x^{3}$

$10 x^{2}$

$0 x$

$31$

$x^{4}$

$0$

$5 x^{2}$

$0 x$

$31$

Step 8

Multiply the new quotient term by the divisor.

$x^{2}$

$0 x$

$5$

$x^{2}$

$0 x$

$5$

$x^{4}$

$0 x^{3}$

$10 x^{2}$

$0 x$

$31$

$x^{4}$

$0$

$5 x^{2}$

$0 x$

$31$

$5 x^{2}$

$0$

$25$

Step 9

The expression needs to be subtracted from the dividend, so change all the signs in $- 5 x^{2} + 0 + 25$

						$x^{2}$	+	$0 x$	-	$5$
$x^{2}$	+	$0 x$	-	$5$		$x^{4}$	+	$0 x^{3}$	-	$10 x^{2}$	+	$0 x$	+	$31$
					-	$x^{4}$	-	$0$	+	$5 x^{2}$
									-	$5 x^{2}$	+	$0 x$	+	$31$
									+	$5 x^{2}$	-	$0$	-	$25$

Step 10

After changing the signs, add the last dividend from the multiplied polynomial to find the new dividend.

						$x^{2}$	+	$0 x$	-	$5$
$x^{2}$	+	$0 x$	-	$5$		$x^{4}$	+	$0 x^{3}$	-	$10 x^{2}$	+	$0 x$	+	$31$
					-	$x^{4}$	-	$0$	+	$5 x^{2}$
									-	$5 x^{2}$	+	$0 x$	+	$31$
									+	$5 x^{2}$	-	$0$	-	$25$
													+	$6$

Step 11

The final answer is the quotient plus the remainder over the divisor.

$x^{2} - 5 + \frac{6}{x^{2} - 5}$