Answer:
x=21.38602241
Step-by-step explanation:
Given: sin(3x)cos(6x) - cos(3x)sin(6x) = -0.9
Rewrite as difference identity: sin(3x-6x)=-0.9
Combine like terms in parentheses: sin(-3x)=-0.9
Take the inverse sine of both sides: -3x=-64.15806724
Divide both sides by -3: x=21.38602241
Refer to the sheet to see all trigonometric identities
