What is the answer to 7=s-9

What are the measures of ∠a, ∠b, ∠c and ∠d? explain how to find each of the angles. measure need asap

Solve 2x2 + 8 = 0 by graphing the related function. there are two solutions: . there are no real number solutions. there are two solutions: 2 and -2

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)