○39.5. а) \( \left\{\begin{array}{l}x-3 y=5, \\ 3 x+2 y=4 ;\end{array}\right. \) б) \( \left\{\begin{array}{l}3 x+y=1, \\ 2 x-5 y=-22 ;\end{array}\right. \) о39.6. а) \( \left\{\begin{array}{l}x+y=4, \\ 4 x-5 y=7 ;\end{array}\right. \) б) \( \left\{\begin{array}{l}x-y=6, \\ 5 x-2 y=-3 ;\end{array}\right. \) о39.7. а) \( \left\{\begin{array}{l}40 x+3 y=-10, \\ 20 x-7 y=-5 ;\end{array}\right. \) б) \( \left\{\begin{array}{l}5 x+2 y=1, \\ 15 x+3 y=3 ;\end{array}\right. \)

г) \( \log _{\frac{1}{5}}^{2}\left(x^{2}+2 x+1\right)-31 \log _{\frac{1}{5}} \frac{x+1}{5}+15<0 \)

Rafael ordered some books online and spent a total of \( \$ 89 \). Each book cost \( \$ 5 \) and he paid a total of \( \$ 4 \) for shipping. How many books did he buy? (a) Write an equation that could be used to answer the question above. First, choose the appropriate form. Then, fill in the blanks with the numbers 89,5 , and 4 . Let \( b \) represent the number of books. \( \square b-\square=\square=\square \) \( b=\square \)

Question 23 Simplify this expression, writing the answer with a rational denominator. \( \frac{1}{\sqrt{3}} \times \frac{1}{\sqrt{3}-1}=\frac{\square+\sqrt{3}}{\square} \)

Solve for \( s \). \[ P=q+10+s \]

Find all the zeros of the quadratic function. \[ y=x^{2}-6 x-16 \] If there is more than one zero, separate them with commas. If there are no zeros, click on "None". zero(s): \( \square \)