Phân thức $\dfrac{{5x - 7}}{{3{x^2} + 6x}}$ xác định khi:

$x \in \left\{ { - 23; - 5; - 3} \right\}$

$x \in \left\{ { - 23; - 5; - 3;15} \right\}$

$x \in \left\{ { - 5; - 3;15} \right\}$

$x \in \left\{ { - 1; - 19;1;19} \right\}$

$P = \dfrac{7}{4}.$

$P = \dfrac{4}{3}.$

$P = \dfrac{{10}}{3}.$

$P =  - \dfrac{{10}}{3}.$

$P = \dfrac{{7 - 3x}}{{x + 4}}$

$P = \dfrac{{ - 3x - 7}}{{x + 4}}$

$P = \dfrac{{ - 3x + 7}}{{x + 4}}$

$P = \dfrac{{3x + 7}}{{x + 4}}$

$P = \dfrac{{7 - 3x}}{{x + 4}}$

$P = \dfrac{{ - 3x - 7}}{{x + 4}}$

$P = \dfrac{{ - 3x + 7}}{{x + 4}}$

$P = \dfrac{{3x + 7}}{{x + 4}}$

\(3x(x - 2)\)    

\(x - 2\)

\(3{x^2}(x - 2)\)

\(3x{(x - 2)^2}\)

\(P = x + y\)

\(P = 5(x - y)\)

 \(P = 5(y - x)\)

\(P = x\)