Resposta :
f(x) = ax+b
f(3) = 5
5 = 3a+b
f(-2) = -5
-5 = -2a+b
3a+b = 5 .(-1)
-2a+b = -5
-3a-b = -5
-2a+b = -5
------------------
-5a = -10 .(-1)
5a = 10 --> a = 10/5 --> a = 2
3a+b = 5 --> 3.2 + b = 5 --> 6+b = 5 --> b = 5-6 --> b = -1
y = ax+b --> y = 2x-1
f(1/2) = 2.(1/2)-1 = 2/2 - 1 = 1-1 = 0
f(3) = 5
5 = 3a+b
f(-2) = -5
-5 = -2a+b
3a+b = 5 .(-1)
-2a+b = -5
-3a-b = -5
-2a+b = -5
------------------
-5a = -10 .(-1)
5a = 10 --> a = 10/5 --> a = 2
3a+b = 5 --> 3.2 + b = 5 --> 6+b = 5 --> b = 5-6 --> b = -1
y = ax+b --> y = 2x-1
f(1/2) = 2.(1/2)-1 = 2/2 - 1 = 1-1 = 0