HELP ME PLEASE!! WILL MARK BRAINLIEST

Which is an equation for the nth terms of the sequence 12,15,18,21

Given: pqrs is a parallelogram prove: pr and qs bisect each other at t

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.