Question

dada a função F(X)=ax+b e sabendo -se que F(3)=5 E F(-2) =-5 calcule F(1/2)

Answer 1

f(x) = ax + b
f(3) = 3a + b = 5
f(2) = 2a + b = -5 .(-1)  

3a + b = 5
-2a-b = 5
------------------
a = 10  

3a+b = 5
3.10 + b = 5
30 + b = 5 
b = 5 - 30
b = -25  

f(x) = 10x - 25
f(1/2) = 10.(1/2) - 25
f(1/2) = 5 - 25
f(1/2) = -20