PLEASE HELP
What are the roots of the equation x^2 + 8x= 0 in simplest a + bi form?

Which pair of angles are vertical angles? ∠1 and ∠4 ∠1 and ∠2 ∠2 and ∠4 ∠2 and ∠3

A33 gram sample of a substance that's used to detect explosives has a k-value of 0.1473. n = noekt no = initial mass (at time t = 0) n = mass at time t k = a positive constant that depends on the substance itself and on the units used to measure time t = time, in days

What are the solutions of the system? solve by graphing. y = -x^2 -6x - 7 y = 2