Answer:(theta) =π only
Step-by-step explanation:
-4cos(theta)+1=5
Subtract 1 from both sides
-4cos(theta)+1-1=5-1
-4cos(theta)=4
Divide both sides by -4
-4cos(theta) ➗ -4=4 ➗ -4
cos(theta)=-1
(theta)=cos(inverse)(-1)
(theta)=180
(theta)=π
