Precalculus Examples

$\frac{6 z}{6 z + 1} - \frac{2 z^{2}}{3 z + 4}$

Step 1

To write $\frac{6 z}{6 z + 1}$ as a fraction with a common denominator, multiply by $\frac{3 z + 4}{3 z + 4}$ .

$\frac{6 z}{6 z + 1} \cdot \frac{3 z + 4}{3 z + 4} - \frac{2 z^{2}}{3 z + 4}$

Step 2

To write $- \frac{2 z^{2}}{3 z + 4}$ as a fraction with a common denominator, multiply by $\frac{6 z + 1}{6 z + 1}$ .

$\frac{6 z}{6 z + 1} \cdot \frac{3 z + 4}{3 z + 4} - \frac{2 z^{2}}{3 z + 4} \cdot \frac{6 z + 1}{6 z + 1}$

Step 3

Write each expression with a common denominator of $(6 z + 1) (3 z + 4)$ , by multiplying each by an appropriate factor of $1$ .

Tap for more steps...

Step 3.1

Multiply $\frac{6 z}{6 z + 1}$ by $\frac{3 z + 4}{3 z + 4}$ .

$\frac{6 z (3 z + 4)}{(6 z + 1) (3 z + 4)} - \frac{2 z^{2}}{3 z + 4} \cdot \frac{6 z + 1}{6 z + 1}$

Step 3.2

Multiply $\frac{2 z^{2}}{3 z + 4}$ by $\frac{6 z + 1}{6 z + 1}$ .

$\frac{6 z (3 z + 4)}{(6 z + 1) (3 z + 4)} - \frac{2 z^{2} (6 z + 1)}{(3 z + 4) (6 z + 1)}$

Step 3.3

Reorder the factors of $(6 z + 1) (3 z + 4)$ .

$\frac{6 z (3 z + 4)}{(3 z + 4) (6 z + 1)} - \frac{2 z^{2} (6 z + 1)}{(3 z + 4) (6 z + 1)}$

Step 4

Combine the numerators over the common denominator.

$\frac{6 z (3 z + 4) - 2 z^{2} (6 z + 1)}{(3 z + 4) (6 z + 1)}$

Step 5

Simplify the numerator.

Tap for more steps...

Step 5.1

Factor $2 z$ out of $6 z (3 z + 4) - 2 z^{2} (6 z + 1)$ .

Tap for more steps...

Step 5.1.1

Factor $2 z$ out of $6 z (3 z + 4)$ .

$\frac{2 z (3 (3 z + 4)) - 2 z^{2} (6 z + 1)}{(3 z + 4) (6 z + 1)}$

Step 5.1.2

Factor $2 z$ out of $- 2 z^{2} (6 z + 1)$ .

$\frac{2 z (3 (3 z + 4)) + 2 z (- z (6 z + 1))}{(3 z + 4) (6 z + 1)}$

Step 5.1.3

Factor $2 z$ out of $2 z (3 (3 z + 4)) + 2 z (- z (6 z + 1))$ .

$\frac{2 z (3 (3 z + 4) - z (6 z + 1))}{(3 z + 4) (6 z + 1)}$

Step 5.2

Apply the distributive property.

$\frac{2 z (3 (3 z) + 3 \cdot 4 - z (6 z + 1))}{(3 z + 4) (6 z + 1)}$

Step 5.3

Multiply $3$ by $3$ .

$\frac{2 z (9 z + 3 \cdot 4 - z (6 z + 1))}{(3 z + 4) (6 z + 1)}$

Step 5.4

Multiply $3$ by $4$ .

$\frac{2 z (9 z + 12 - z (6 z + 1))}{(3 z + 4) (6 z + 1)}$

Step 5.5

Apply the distributive property.

$\frac{2 z (9 z + 12 - z (6 z) - z \cdot 1)}{(3 z + 4) (6 z + 1)}$

Step 5.6

Rewrite using the commutative property of multiplication.

$\frac{2 z (9 z + 12 - 1 \cdot 6 z \cdot z - z \cdot 1)}{(3 z + 4) (6 z + 1)}$

Step 5.7

Multiply $- 1$ by $1$ .

$\frac{2 z (9 z + 12 - 1 \cdot 6 z \cdot z - z)}{(3 z + 4) (6 z + 1)}$

Step 5.8

Simplify each term.

Tap for more steps...

Step 5.8.1

Multiply $z$ by $z$ by adding the exponents.

Tap for more steps...

Step 5.8.1.1

Move $z$ .

$\frac{2 z (9 z + 12 - 1 \cdot 6 (z \cdot z) - z)}{(3 z + 4) (6 z + 1)}$

Step 5.8.1.2

Multiply $z$ by $z$ .

$\frac{2 z (9 z + 12 - 1 \cdot 6 z^{2} - z)}{(3 z + 4) (6 z + 1)}$

Step 5.8.2

Multiply $- 1$ by $6$ .

$\frac{2 z (9 z + 12 - 6 z^{2} - z)}{(3 z + 4) (6 z + 1)}$

Step 5.9

Subtract $z$ from $9 z$ .

$\frac{2 z (8 z + 12 - 6 z^{2})}{(3 z + 4) (6 z + 1)}$

Step 5.10

Reorder terms.

$\frac{2 z (- 6 z^{2} + 8 z + 12)}{(3 z + 4) (6 z + 1)}$

Step 5.11

Factor $2$ out of $- 6 z^{2} + 8 z + 12$ .

Tap for more steps...

Step 5.11.1

Factor $2$ out of $- 6 z^{2}$ .

$\frac{2 z (2 (- 3 z^{2}) + 8 z + 12)}{(3 z + 4) (6 z + 1)}$

Step 5.11.2

Factor $2$ out of $8 z$ .

$\frac{2 z (2 (- 3 z^{2}) + 2 (4 z) + 12)}{(3 z + 4) (6 z + 1)}$

Step 5.11.3

Factor $2$ out of $12$ .

$\frac{2 z (2 (- 3 z^{2}) + 2 (4 z) + 2 (6))}{(3 z + 4) (6 z + 1)}$

Step 5.11.4

Factor $2$ out of $2 (- 3 z^{2}) + 2 (4 z)$ .

$\frac{2 z (2 (- 3 z^{2} + 4 z) + 2 (6))}{(3 z + 4) (6 z + 1)}$

Step 5.11.5

Factor $2$ out of $2 (- 3 z^{2} + 4 z) + 2 (6)$ .

$\frac{2 z (2 (- 3 z^{2} + 4 z + 6))}{(3 z + 4) (6 z + 1)}$

$\frac{2 z \cdot 2 (- 3 z^{2} + 4 z + 6)}{(3 z + 4) (6 z + 1)}$

Step 5.12

Multiply $2$ by $2$ .

$\frac{4 z (- 3 z^{2} + 4 z + 6)}{(3 z + 4) (6 z + 1)}$

Step 6

Simplify with factoring out.

Tap for more steps...

Step 6.1

Factor $- 1$ out of $- 3 z^{2}$ .

$\frac{4 z (- (3 z^{2}) + 4 z + 6)}{(3 z + 4) (6 z + 1)}$

Step 6.2

Factor $- 1$ out of $4 z$ .

$\frac{4 z (- (3 z^{2}) - (- 4 z) + 6)}{(3 z + 4) (6 z + 1)}$

Step 6.3

Factor $- 1$ out of $- (3 z^{2}) - (- 4 z)$ .

$\frac{4 z (- (3 z^{2} - 4 z) + 6)}{(3 z + 4) (6 z + 1)}$

Step 6.4

Rewrite $6$ as $- 1 (- 6)$ .

$\frac{4 z (- (3 z^{2} - 4 z) - 1 (- 6))}{(3 z + 4) (6 z + 1)}$

Step 6.5

Factor $- 1$ out of $- (3 z^{2} - 4 z) - 1 (- 6)$ .

$\frac{4 z (- (3 z^{2} - 4 z - 6))}{(3 z + 4) (6 z + 1)}$

Step 6.6

Simplify the expression.

Tap for more steps...

Step 6.6.1

Rewrite $- (3 z^{2} - 4 z - 6)$ as $- 1 (3 z^{2} - 4 z - 6)$ .

$\frac{4 z (- 1 (3 z^{2} - 4 z - 6))}{(3 z + 4) (6 z + 1)}$

Step 6.6.2

Move the negative in front of the fraction.

$- \frac{(4 z) (3 z^{2} - 4 z - 6)}{(3 z + 4) (6 z + 1)}$

Step 6.6.3

Reorder factors in $- \frac{(4 z) (3 z^{2} - 4 z - 6)}{(3 z + 4) (6 z + 1)}$ .

$- \frac{4 z (3 z^{2} - 4 z - 6)}{(3 z + 4) (6 z + 1)}$