Bonjour voilà la réponse
f(x) = -3x+5
. x = 0
f(0) = -3*0+5 = 0+5 = 5
. f(x) = 0
-3x+5 = 0
-3x = -5
x = -5/-3
x = 5/3
. x = 2
f(2) = -3*2+5 = -6+5 = -1
. f(x) = 2
-3x+5 = 2
-3x = 2-5
-3x = -3
x = -3/-3
x = 1
. x = -4
f(-4) = -3*-4+5 = 12+5 = 17
Voilà j'espère avoir pu t'aider ^^