Simplity the following expression. \( \begin{array}{l}(-1)(x-4)+3(x+2) \\ 2 x+10 \\ 2 x+2 \\ 2 x-2 \\ 2 x+6\end{array} \)

81 If the equation \( x^{2}-6 x+9=\mathrm{b} \) has two real distinct roots, then \( \mathrm{b} \in \ldots \ldots . . . \). . \( \begin{array}{llll}\text { (a) } R & \text { (b) }]-\infty, 0] & \text { (c) }]-\infty, 0[ & \text { (d) }] 0, \infty[ \end{array} \)

Bài 3. Viết điều kiện xác định và rút gọn các biểu thức sa s-( \( \left.x-3-\frac{x}{x-3}+\frac{9}{x}\right): \frac{2 x-2}{x} \)

19. On the set of axes below, draw the graph of the equation \( y=-\frac{3}{4} x+3 \).

Mathematics If \( x \) varies inversely as the seware \( y \), ohen \( x=27, y=9 \) find the equation connecting \( x \) and \( y \) find \( x \) colen \( y=10 \)

Mathematics If \( x \) taries inversely as the \( y \), when \( x=27, y=9 \) find the equation connectung \( x \)