bonjour
f ( - 1 ) = 2
f (0) = 1.5
f ( 3) = 0
f ( 5 ) = - 1
7 a pour image - 2
f ( - 1 ) = 2 et f ( 0 ) = 1.5
( 1.5 - 2 ) / ( 0 + 1 ) = - 0.5
ax = - 0.5
f (0) = 1.5 donc b = 1.5
f ( x) = - 0. 5x + 1.5
g (x) = 2 x + 3
2 x + 3 = - 0.5 x + 1.5
2 x + 0.5 x = 1.5 - 3
2.5 x = - 1.5
x = - 0 .6
2 x + 3 < - 0.5 x + 1.5
2 x + 0.5 x < 1.5 - 3
2.5 x < - 1.5
x < - 0.6