What quantity measures the amount of matter in an object?

volume
temperature
mass
density

The perimeter of a movie screen is 54 meters. the screen is 18 meters wide. how tall is it?

What are the solutions of the system? solve by graphing. y = -x^2 -6x - 7 y = 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.