Solve by the addition method. (If there is no solution, enter NO SOLUTION. Use the parameters \( x \) and \( y \) as necessary.) \[ \begin{array}{r}3 x+4 y=28 \\ 2 x+y=12\end{array} \] \( (x, y)=\left(\begin{array}{r}\square\end{array}\right. \)

(ס) \( \frac{4(a-9)}{36(9-a) x^{3}} \)

5. Solve \( x^{2}+4 x+3>0 \)

(12) If \( 4 n \geq 9 \), what is the least possible value of \( 4 n+1 ? \)

FACTORIZAR APLICANDO CASOS COMBINADOS DE FACTDRES A) \( \cdot x^{3}+5 x^{2}-4 x-20 \) B) \( \cdot 75 x^{5}+60 x^{4}+12 x^{3} \) C) \( \cdot 2 x^{2}-18 \) d) \( x^{3}+x^{2}-9 x-9 \) e) \( x^{4}-81 \)

1.Решить уравнение: \( \begin{array}{lll}\text { a) } \sqrt{x+3}=\sqrt{5-x} & \text { б) } \quad \sqrt{12+3 x}=2 & \text { в) } \quad x=1+\sqrt{x+11}\end{array} \)