Question

Dada a função f(x) = ax + b e sabendo que f (3) = 5 e f(-2) = -5, calcule 1/2

Answer 1

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
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-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