2cosx-1=.0068 find x in degrees

60 degree

Step-by-step explanation:

adding 1 both sides of equation

2cos x -1+1 = 0.0068 +1

2cosx = 0.9932

dividing by 2 both sides

cosx = 0.9932 / 2

cosx =0.4966

x= cos^-1(0.4966)

x=60 degree

correct answer is infinitely many solutions

step-by-step explanation:

2(2x + 3) = -4 + 2(2x + 5)

solving the above equation:

4x + 6 = -4 +4x +10

combining like terms

4x -4x = -4+10-6

0=0

since both sides are 0=0, we end up into true statement it means it has infinite many solutions.

so correct answer is infinitely many solutions

option (b) is correct

step-by-step explanation:

to find the solution of this system, we need to convert it into reduced row-echelon form. we have,

after applying row operations r2 -> r2/2 and r3 -> r3/3, we get,