What is the equation of the line tangent to the circle at the given point x^2+y^2=20 at (-4,2)

Find the solution set of this inequality. enter your answer in interval notation using grouping symbols. |8x-4| ≤ 12

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?

Can someone me with the property questions for 12 13 and 14 plz