Pre-Algebra Examples

$\frac{5 x^{4} + 8 x - 9}{x^{2} - 4}$

Step 1

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

$x^{2}$

$0 x$

$4$

$5 x^{4}$

$0 x^{3}$

$0 x^{2}$

$8 x$

$9$

Step 2

Divide the highest order term in the dividend $5 x^{4}$ by the highest order term in divisor $x^{2}$ .

$5 x^{2}$

$x^{2}$

$0 x$

$4$

$5 x^{4}$

$0 x^{3}$

$0 x^{2}$

$8 x$

$9$

Step 3

Multiply the new quotient term by the divisor.

$5 x^{2}$

$x^{2}$

$0 x$

$4$

$5 x^{4}$

$0 x^{3}$

$0 x^{2}$

$8 x$

$9$

$5 x^{4}$

$0$

$20 x^{2}$

Step 4

The expression needs to be subtracted from the dividend, so change all the signs in $5 x^{4} + 0 - 20 x^{2}$

$5 x^{2}$

$x^{2}$

$0 x$

$4$

$5 x^{4}$

$0 x^{3}$

$0 x^{2}$

$8 x$

$9$

$5 x^{4}$

$0$

$20 x^{2}$

Step 5

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

$5 x^{2}$

$x^{2}$

$0 x$

$4$

$5 x^{4}$

$0 x^{3}$

$0 x^{2}$

$8 x$

$9$

$5 x^{4}$

$0$

$20 x^{2}$

Step 6

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

$5 x^{2}$

$x^{2}$

$0 x$

$4$

$5 x^{4}$

$0 x^{3}$

$0 x^{2}$

$8 x$

$9$

$5 x^{4}$

$0$

$20 x^{2}$

$8 x$

$9$

Step 7

Divide the highest order term in the dividend $20 x^{2}$ by the highest order term in divisor $x^{2}$ .

$5 x^{2}$

$0 x$

$20$

$x^{2}$

$0 x$

$4$

$5 x^{4}$

$0 x^{3}$

$0 x^{2}$

$8 x$

$9$

$5 x^{4}$

$0$

$20 x^{2}$

$8 x$

$9$

Step 8

Multiply the new quotient term by the divisor.

$5 x^{2}$

$0 x$

$20$

$x^{2}$

$0 x$

$4$

$5 x^{4}$

$0 x^{3}$

$0 x^{2}$

$8 x$

$9$

$5 x^{4}$

$0$

$20 x^{2}$

$8 x$

$9$

$20 x^{2}$

$0$

$80$

Step 9

The expression needs to be subtracted from the dividend, so change all the signs in $20 x^{2} + 0 - 80$

$5 x^{2}$

$0 x$

$20$

$x^{2}$

$0 x$

$4$

$5 x^{4}$

$0 x^{3}$

$0 x^{2}$

$8 x$

$9$

$5 x^{4}$

$0$

$20 x^{2}$

$8 x$

$9$

$20 x^{2}$

$0$

$80$

Step 10

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

$5 x^{2}$

$0 x$

$20$

$x^{2}$

$0 x$

$4$

$5 x^{4}$

$0 x^{3}$

$0 x^{2}$

$8 x$

$9$

$5 x^{4}$

$0$

$20 x^{2}$

$8 x$

$9$

$20 x^{2}$

$0$

$80$

$8 x$

$71$

Step 11

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

$5 x^{2} + 20 + \frac{8 x + 71}{x^{2} - 4}$