What are the upper and lower quartilles of the following plots?

4,5,8,9,10,15,15,20

Solve the equation 3x2 + 19x + 9 = 0 to the nearest tenth.

The length of triangle base is 26. a line, which is parallel to the base divides the triangle into two equal area parts. find the length of the segment between triangle legs.

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