91Ó°ÊÓ

Graph the inequality. $$y \geq 2$$

Finding the Inverse of a Matrix Find the inverse of the matrix if it exists. $$\left[\begin{array}{rr}-3 & -5 \\\2 & 3\end{array}\right]$$

Perform the matrix operation, or if it is impossible, explain why. $$2\left[\begin{array}{lll} 1 & 1 & 0 \\ 1 & 0 & 1 \\ 0 & 1 & 1 \end{array}\right]+\left[\begin{array}{ll} 1 & 1 \\ 2 & 1 \\ 3 & 1 \end{array}\right]$$

Write the augmented matrix for the system of linear equations. $$\left\\{\begin{array}{rr} -x \quad+z= & -1 \\ 3 y-2 z= & 7 \\ x-y+3 z= & 3 \end{array}\right.$$

Graph the inequality. $$x \leq-1$$

Use the elimination method to find all solutions of the system of equations. $$\left\\{\begin{aligned} 2 x^{2}+4 y &=13 \\ x^{2}-y^{2} &=\frac{7}{2} \end{aligned}\right.$$

Finding the Inverse of a Matrix Find the inverse of the matrix if it exists. $$\left[\begin{array}{ll}3 & 4 \\\7 & 9\end{array}\right]$$

Write the form of the partial fraction decomposition of the function (as in Example 4 ). Do not determine the numerical values of the coefficients. $$\frac{1}{\left(x^{3}-1\right)\left(x^{2}-1\right)}$$

Use back-substitution to solve the triangular system. \(\left\\{\begin{aligned} 4 x+3 z &=10 \\ 2 y-z &=-6 \\ \frac{1}{2} z &=4 \end{aligned}\right.\)

Finding the Inverse of a Matrix Find the inverse of the matrix if it exists. $$\left[\begin{array}{rr}2 & 5 \\\\-5 & -13\end{array}\right]$$