7. Systems of Equations & Matrices

What is the value of x if = 9?

Evaluate each determinant. See Example 1.

Evaluate each determinant in Exercises 1–10. - 5 - 1- 2 - 7

Evaluate each determinant. See Example 1.

Evaluate each determinant in Exercises 1–10. 1/2 1/21/8 - 3/4

Evaluate each determinant. See Example 1.

Evaluate each determinant. See Example 1.

For Exercises 11–22, use Cramer's Rule to solve each system. 12x + 3y = 152x - 3y = 13

Evaluate each determinant. See Example 1.

For Exercises 11–22, use Cramer's Rule to solve each system. 4x - 5y = 172x + 3y = 3

For Exercises 11–22, use Cramer's Rule to solve each system. x + 2y = 33x - 4y = 4

Find the cofactor of each element in the second row of each matrix. See Example 2.

Find the cofactor of each element in the second row of each matrix. See Example 2.

For Exercises 11–22, use Cramer's Rule to solve each system. 3x - 4y = 42x + 2y = 12

Evaluate each determinant. See Example 3.