Bonjour :
9α + β = 0
16α + β = 3.5
9α = -β
16α + β = 3.5
α = -β/9
16α + β = 3.5
α = -β/9
16(-β/9) + β = 3.5
α = -β/9
-16β/9 + β = 3.5
α = -β/9
-16β/9 + 9β/9 = 3.5
α = -β/9
-7β/9 = 3.5
α = -β/9
-7β = 3.5×9
α = -β/9
-7β = 31.5
α = -β/9
β = 31.5/-7
α = -β/9
β = -4.5
α = -(-4.5)/9
β = -4.5
α = 4.5/9
β = -4.5
α = 0.5
β = -4.5
Vérification :
9α + β = 0
9×0.5 + (-4.5) = 0
4.5 - 4.5 = 0
0 = 0
16α + β = 3.5
16×0.5 + (-4.5) = 3.5
8 - 4.5 = 3.5
3.5 = 3.5
J’espère t'avoir t'aider
