Finite Math Examples

$\frac{x - 7}{2 x^{2} + 7 x + 3} - \frac{x + 4}{2 x^{2} - 9 x - 5}$

Step 1

Simplify each term.

Tap for more steps...

Step 1.1

Factor by grouping.

Tap for more steps...

Step 1.1.1

For a polynomial of the form $a x^{2} + b x + c$ , rewrite the middle term as a sum of two terms whose product is $a \cdot c = 2 \cdot 3 = 6$ and whose sum is $b = 7$ .

Tap for more steps...

Step 1.1.1.1

Factor $7$ out of $7 x$ .

$\frac{x - 7}{2 x^{2} + 7 (x) + 3} - \frac{x + 4}{2 x^{2} - 9 x - 5}$

Step 1.1.1.2

Rewrite $7$ as $1$ plus $6$

$\frac{x - 7}{2 x^{2} + (1 + 6) x + 3} - \frac{x + 4}{2 x^{2} - 9 x - 5}$

Step 1.1.1.3

Apply the distributive property.

$\frac{x - 7}{2 x^{2} + 1 x + 6 x + 3} - \frac{x + 4}{2 x^{2} - 9 x - 5}$

Step 1.1.1.4

Multiply $x$ by $1$ .

$\frac{x - 7}{2 x^{2} + x + 6 x + 3} - \frac{x + 4}{2 x^{2} - 9 x - 5}$

Step 1.1.2

Factor out the greatest common factor from each group.

Tap for more steps...

Step 1.1.2.1

Group the first two terms and the last two terms.

$\frac{x - 7}{(2 x^{2} + x) + 6 x + 3} - \frac{x + 4}{2 x^{2} - 9 x - 5}$

Step 1.1.2.2

Factor out the greatest common factor (GCF) from each group.

$\frac{x - 7}{x (2 x + 1) + 3 (2 x + 1)} - \frac{x + 4}{2 x^{2} - 9 x - 5}$

Step 1.1.3

Factor the polynomial by factoring out the greatest common factor, $2 x + 1$ .

$\frac{x - 7}{(2 x + 1) (x + 3)} - \frac{x + 4}{2 x^{2} - 9 x - 5}$

Step 1.2

Factor by grouping.

Tap for more steps...

Step 1.2.1

For a polynomial of the form $a x^{2} + b x + c$ , rewrite the middle term as a sum of two terms whose product is $a \cdot c = 2 \cdot - 5 = - 10$ and whose sum is $b = - 9$ .

Tap for more steps...

Step 1.2.1.1

Factor $- 9$ out of $- 9 x$ .

$\frac{x - 7}{(2 x + 1) (x + 3)} - \frac{x + 4}{2 x^{2} - 9 (x) - 5}$

Step 1.2.1.2

Rewrite $- 9$ as $1$ plus $- 10$

$\frac{x - 7}{(2 x + 1) (x + 3)} - \frac{x + 4}{2 x^{2} + (1 - 10) x - 5}$

Step 1.2.1.3

Apply the distributive property.

$\frac{x - 7}{(2 x + 1) (x + 3)} - \frac{x + 4}{2 x^{2} + 1 x - 10 x - 5}$

Step 1.2.1.4

Multiply $x$ by $1$ .

$\frac{x - 7}{(2 x + 1) (x + 3)} - \frac{x + 4}{2 x^{2} + x - 10 x - 5}$

Step 1.2.2

Factor out the greatest common factor from each group.

Tap for more steps...

Step 1.2.2.1

Group the first two terms and the last two terms.

$\frac{x - 7}{(2 x + 1) (x + 3)} - \frac{x + 4}{(2 x^{2} + x) - 10 x - 5}$

Step 1.2.2.2

Factor out the greatest common factor (GCF) from each group.

$\frac{x - 7}{(2 x + 1) (x + 3)} - \frac{x + 4}{x (2 x + 1) - 5 (2 x + 1)}$

Step 1.2.3

Factor the polynomial by factoring out the greatest common factor, $2 x + 1$ .

$\frac{x - 7}{(2 x + 1) (x + 3)} - \frac{x + 4}{(2 x + 1) (x - 5)}$

Step 2

To write $\frac{x - 7}{(2 x + 1) (x + 3)}$ as a fraction with a common denominator, multiply by $\frac{x - 5}{x - 5}$ .

$\frac{x - 7}{(2 x + 1) (x + 3)} \cdot \frac{x - 5}{x - 5} - \frac{x + 4}{(2 x + 1) (x - 5)}$

Step 3

To write $- \frac{x + 4}{(2 x + 1) (x - 5)}$ as a fraction with a common denominator, multiply by $\frac{x + 3}{x + 3}$ .

$\frac{x - 7}{(2 x + 1) (x + 3)} \cdot \frac{x - 5}{x - 5} - \frac{x + 4}{(2 x + 1) (x - 5)} \cdot \frac{x + 3}{x + 3}$

Step 4

Write each expression with a common denominator of $(2 x + 1) (x + 3) (x - 5)$ , by multiplying each by an appropriate factor of $1$ .

Tap for more steps...

Step 4.1

Multiply $\frac{x - 7}{(2 x + 1) (x + 3)}$ by $\frac{x - 5}{x - 5}$ .

$\frac{(x - 7) (x - 5)}{(2 x + 1) (x + 3) (x - 5)} - \frac{x + 4}{(2 x + 1) (x - 5)} \cdot \frac{x + 3}{x + 3}$

Step 4.2

Multiply $\frac{x + 4}{(2 x + 1) (x - 5)}$ by $\frac{x + 3}{x + 3}$ .

$\frac{(x - 7) (x - 5)}{(2 x + 1) (x + 3) (x - 5)} - \frac{(x + 4) (x + 3)}{(2 x + 1) (x - 5) (x + 3)}$

Step 4.3

Reorder the factors of $(2 x + 1) (x - 5) (x + 3)$ .

$\frac{(x - 7) (x - 5)}{(2 x + 1) (x + 3) (x - 5)} - \frac{(x + 4) (x + 3)}{(2 x + 1) (x + 3) (x - 5)}$

Step 5

Combine the numerators over the common denominator.

$\frac{(x - 7) (x - 5) - (x + 4) (x + 3)}{(2 x + 1) (x + 3) (x - 5)}$

Step 6

Simplify the numerator.

Tap for more steps...

Step 6.1

Expand $(x - 7) (x - 5)$ using the FOIL Method.

Tap for more steps...

Step 6.1.1

Apply the distributive property.

$\frac{x (x - 5) - 7 (x - 5) - (x + 4) (x + 3)}{(2 x + 1) (x + 3) (x - 5)}$

Step 6.1.2

Apply the distributive property.

$\frac{x \cdot x + x \cdot - 5 - 7 (x - 5) - (x + 4) (x + 3)}{(2 x + 1) (x + 3) (x - 5)}$

Step 6.1.3

Apply the distributive property.

$\frac{x \cdot x + x \cdot - 5 - 7 x - 7 \cdot - 5 - (x + 4) (x + 3)}{(2 x + 1) (x + 3) (x - 5)}$

Step 6.2

Simplify and combine like terms.

Tap for more steps...

Step 6.2.1

Simplify each term.

Tap for more steps...

Step 6.2.1.1

Multiply $x$ by $x$ .

$\frac{x^{2} + x \cdot - 5 - 7 x - 7 \cdot - 5 - (x + 4) (x + 3)}{(2 x + 1) (x + 3) (x - 5)}$

Step 6.2.1.2

Move $- 5$ to the left of $x$ .

$\frac{x^{2} - 5 \cdot x - 7 x - 7 \cdot - 5 - (x + 4) (x + 3)}{(2 x + 1) (x + 3) (x - 5)}$

Step 6.2.1.3

Multiply $- 7$ by $- 5$ .

$\frac{x^{2} - 5 x - 7 x + 35 - (x + 4) (x + 3)}{(2 x + 1) (x + 3) (x - 5)}$

Step 6.2.2

Subtract $7 x$ from $- 5 x$ .

$\frac{x^{2} - 12 x + 35 - (x + 4) (x + 3)}{(2 x + 1) (x + 3) (x - 5)}$

Step 6.3

Apply the distributive property.

$\frac{x^{2} - 12 x + 35 + (- x - 1 \cdot 4) (x + 3)}{(2 x + 1) (x + 3) (x - 5)}$

Step 6.4

Multiply $- 1$ by $4$ .

$\frac{x^{2} - 12 x + 35 + (- x - 4) (x + 3)}{(2 x + 1) (x + 3) (x - 5)}$

Step 6.5

Expand $(- x - 4) (x + 3)$ using the FOIL Method.

Tap for more steps...

Step 6.5.1

Apply the distributive property.

$\frac{x^{2} - 12 x + 35 - x (x + 3) - 4 (x + 3)}{(2 x + 1) (x + 3) (x - 5)}$

Step 6.5.2

Apply the distributive property.

$\frac{x^{2} - 12 x + 35 - x \cdot x - x \cdot 3 - 4 (x + 3)}{(2 x + 1) (x + 3) (x - 5)}$

Step 6.5.3

Apply the distributive property.

$\frac{x^{2} - 12 x + 35 - x \cdot x - x \cdot 3 - 4 x - 4 \cdot 3}{(2 x + 1) (x + 3) (x - 5)}$

Step 6.6

Simplify and combine like terms.

Tap for more steps...

Step 6.6.1

Simplify each term.

Tap for more steps...

Step 6.6.1.1

Multiply $x$ by $x$ by adding the exponents.

Tap for more steps...

Step 6.6.1.1.1

Move $x$ .

$\frac{x^{2} - 12 x + 35 - (x \cdot x) - x \cdot 3 - 4 x - 4 \cdot 3}{(2 x + 1) (x + 3) (x - 5)}$

Step 6.6.1.1.2

Multiply $x$ by $x$ .

$\frac{x^{2} - 12 x + 35 - x^{2} - x \cdot 3 - 4 x - 4 \cdot 3}{(2 x + 1) (x + 3) (x - 5)}$

Step 6.6.1.2

Multiply $3$ by $- 1$ .

$\frac{x^{2} - 12 x + 35 - x^{2} - 3 x - 4 x - 4 \cdot 3}{(2 x + 1) (x + 3) (x - 5)}$

Step 6.6.1.3

Multiply $- 4$ by $3$ .

$\frac{x^{2} - 12 x + 35 - x^{2} - 3 x - 4 x - 12}{(2 x + 1) (x + 3) (x - 5)}$

Step 6.6.2

Subtract $4 x$ from $- 3 x$ .

$\frac{x^{2} - 12 x + 35 - x^{2} - 7 x - 12}{(2 x + 1) (x + 3) (x - 5)}$

Step 6.7

Subtract $x^{2}$ from $x^{2}$ .

$\frac{- 12 x + 35 + 0 - 7 x - 12}{(2 x + 1) (x + 3) (x - 5)}$

Step 6.8

Add $- 12 x$ and $0$ .

$\frac{- 12 x + 35 - 7 x - 12}{(2 x + 1) (x + 3) (x - 5)}$

Step 6.9

Subtract $7 x$ from $- 12 x$ .

$\frac{- 19 x + 35 - 12}{(2 x + 1) (x + 3) (x - 5)}$

Step 6.10

Subtract $12$ from $35$ .

$\frac{- 19 x + 23}{(2 x + 1) (x + 3) (x - 5)}$

Step 7

Simplify with factoring out.

Tap for more steps...

Step 7.1

Factor $- 1$ out of $- 19 x$ .

$\frac{- (19 x) + 23}{(2 x + 1) (x + 3) (x - 5)}$

Step 7.2

Rewrite $23$ as $- 1 (- 23)$ .

$\frac{- (19 x) - 1 (- 23)}{(2 x + 1) (x + 3) (x - 5)}$

Step 7.3

Factor $- 1$ out of $- (19 x) - 1 (- 23)$ .

$\frac{- (19 x - 23)}{(2 x + 1) (x + 3) (x - 5)}$

Step 7.4

Simplify the expression.

Tap for more steps...

Step 7.4.1

Rewrite $- (19 x - 23)$ as $- 1 (19 x - 23)$ .

$\frac{- 1 (19 x - 23)}{(2 x + 1) (x + 3) (x - 5)}$

Step 7.4.2

Move the negative in front of the fraction.

$- \frac{19 x - 23}{(2 x + 1) (x + 3) (x - 5)}$