which is a function? {(8,9),(−2,9),(7,5),(−4,−7)} {(−5,−7),(−5,4),(−2,−8),(3,5)} {(8,0),(−4,−2),(7,1),(0,0)} {(−8,3),(−5,−7),(−4,5),(9,3)}

Step-by-step explanation:

Function means that for each x we get y, and no no x gives two different y-es

{(−5,−7),(−5,4),(−2,−8),(3,5)}  for x = -5 we have two different y-es therefore its not function

hello from mrbilldoesmath!

answer:

a(n) - a(n-1) -3

discussion:

this ones a bit interesting. given a(n) = 5 - 3n consider this:

a(n-1) = 5 - 3(n-1)

          = (5 - 3n) + 3             => but a(n) = 5 - 3n, the first term

          = a(n)   + 3                 => subtract 3 from both sides

a(n-1) -3 = a(n)  

or

a(n) - a(n-1) -3

you,

mrb

idk

step-by-step explanation:

i don't know