2) For the linear function \( f \) if \( f(2)=2 \) and \( f(4)=5 \). chen for whal value of \( x \) is \( f(x)=0 \) ? \( \begin{array}{lllll}\text { (A) } \frac{2}{3} & \text { (B) } \frac{3}{4} & \text { (C) } 1 & \text { (D) } \frac{4}{3} & \text { (E) } \frac{3}{2}\end{array} \)

2. Find the domain and perform each of the following indicated operations. \[ \begin{array}{ll}\text { a. } \frac{x-1}{x+2}+\frac{x+3}{x^{2}+6 x+5} & \text { c. } \frac{x-1}{x+2} \times \frac{x+3}{x^{2}+6 x+5} \\ \text { b. } \frac{x-1}{x+2}-\frac{x+3}{x^{2}+6 x+5} & \text { d. } \frac{x-1}{x+2} \div \frac{x+3}{x^{2}+6 x+5}\end{array} \]

\( \begin{array}{l}\qquad x=8 \\ \text { So, length of the given rectangle }=(8+9) \mathrm{cm}=17 \mathrm{~cm} \\ \text { And, breadt of the given rectangle }=8 \mathrm{~cm} .\end{array} \) EXERCISE 15 B 1. 17 less than four times a number is 11 . Find the number.

15. Determine whether the function \( f: \mathbf{Z} \times \mathbf{Z} \rightarrow \mathbf{Z} \) is onto if a) \( f(m, n)=m+n \). b) \( f(m, n)=m^{2}+n^{2} \). c) \( f(m, n)=m \). d) \( f(m, n)=|n| \). e) \( f(m, n)=m-n \).

1. Dado o Polinómio \( P(x)=x^{3}-2 x^{2}+10 \), determine: a) O grau do polinómio \( \begin{array}{l}\text { b) O coeficiente principal } \\ \text { b) O Coeficiente independente. } \\ \text { (1 valor) } \\ \text { d) } x=-2 \text { é uma raíz do polinómio? } \\ \text { (1 valor) } \\ \text { 2. Dado os polinómios } P(x)=x^{2}+x-6 \text {, determine: } \\ \text { a) O Dobro da quinta parte de } \mathrm{P}(\mathrm{x}) \\ \text { b) } P(3)\end{array} \)

a) \( \frac{2}{7} x+\frac{5 x}{7}-3 x=8 \)