Fill in the blank so that the resulting statement is true. The first step in solving \( \frac{2}{x}-\frac{3}{y}=\frac{4}{z} \) for \( z \) is to multiply both sides of the equation by the least common denominator, which is

3Ldentifica y realiza los siguentes productos notables de polinomios: \( \begin{array}{ll}\text { A) }(2 a b+7 c)(2 a b-7 c)=\quad & \text { b) }(5 a-2 b)^{2}=\end{array} \)

23. \( x^{3}-3 x=-1 \) olarsa, \( x^{2}+\frac{1}{x^{2}} \) ifadəsinin qiymatini tapın.

Jason earns an hourly wage of \( y \) dollars. If he works \( h \) hours in a week, write a linear expression representing his weekly earnings.

\( 6 a ^ { 2 } + 3 a c + 4 a b + 2 b \)

4. Realiza las operaciones indicadas y simplifica el lesultado: \( \begin{array}{ll}\text { A) } \frac{x^{2}-64}{2 x^{2}+16 x}= & \frac{\text { B) } 3 x-9}{x^{2}-9 x+18}=\end{array} \)