How to solve multi step equations with variables on both sides and parentheses?

Evaluate cos2θ for cosθ = square root of 3/2

Which statements are true? check all that apply. the line x = 0 is perpendicular to the line y = –3. all lines that are parallel to the y-axis are vertical lines. all lines that are perpendicular to the x-axis have a slope of 0. the equation of the line parallel to the x-axis that passes through the point (2, –6) is x = 2. the equation of the line perpendicular to the y-axis that passes through the point (–5, 1) is y = 1.

Acabinmaker buys 3.5 liters of oat varnish the varnish cost $4.95 per liter what is the total cost of 3.5 liters