−9+x ≤ 4
what is x

(so it passes:iuyhtgfghuytg)

How many sides does a regular polygon have if each exterior angle measures 72a.3b.4c.5d.6

Which math sentence can be used to determine if the triangle is a right triangle?

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)