HELP HELP HELP What is the explicit rule for the arithmetic sequence?

20.5, 18, 15.5, 13, 10.5, ...

an=23+2.5n

an=20.5−2.5n

an=20.5+2.5n

an=23−2.5n

Evaluate the discriminant of each equation. tell how many solutions each equation has and whether the solutions are real or imaginary. x^2 - 4x - 5 = 0

Michelle is planting flowers in her garden. she wants the ratio of daises to carnations to be 3 to 2. michelle wants to plant a total of 35 flowers. how many daises should she plant?

Julie begins counting backwards from 1000 by 2’s and at the same time tony begins counting forward from 100 by 3’s.   if they count at the same rate, what number will they say at the same time?