The second side of a triangle is three times its first side, and its third side is five more than its first side. The triangle perimeter is 20 unit. What is the length of the second side?

Plz me i need i will give a brain

Find the height of a square pyramid that has the volume of 32 ft.³ and a base lengthof 4 feet

The position of a moving particle is given by the position function: f(t)=-9t-t^2-0.2t^3+0.1t^4 a. at what time does the particle reverse direction? b. when is the displacement positive? (round one decimal place and answer in interval notation) c. when is the displacement negative? (round one decimal place and answer in interval notation) d. when is the particle’s acceleration positive? (round one decimal place and answer in interval notation) e. when is the particle’s acceleration negative? (round one decimal place and answer in interval notation)