Help with setting up the problem to solve

In the problem I am being asked to solve for the value of X. I have tried setting up right triangles and a mix of right and oblique triangls but have not been able to get the right combination. The value of A is 3.5 and the answer of X is 1.8376. The book gives the answer and we construct the problem

Inverse circular functions

Solve for: sin-1 (cos x) (Limit solution to an acute angle.)

Matrix operations

#5 M is a (3*3) matrix, use the identity matrix to find the inverse of M= 1 5 42 -7 -34 -287 28 136 1149 List the following M^-1 (1,2), A(2,2).,(2,3)

Matrix operations

Find the determinant of the following matrix and find the Area of the parrallelogram formed by the two vectors. Matrix: i j k 1 1 -3 0 -6 5

Matrix operations

Let AX =C, If B is the inverse of A, then the solve the matrix X Matix B(3x3)row 1 = -17 78 24 row 2 = -3 13 4 row 3 = -10 16 5 Matrix C(1x3) row 1 = 24 row 2 = -686 row 3 = 2246