Vertex Form y=a(x-h)^2+k what does each variable represent if they were in a problem.

The fence around a quadrilateral-shaped pasture is 3a^2+15a+9 long. three sides of the fence have the following lengths: 5a, 10a-2, a^2-7. what is the length of the fourth side of the fence?

What is the slope of the line that contains the points (-2,1) and (0,-3)

Jayne is studying urban planning and finds that her town is decreasing in population by 3% each year. the population of her town is changing by a constant rate. true or false?