Question

Considere f(x) = mx + b, f(-2) = 3 e f(4) = 1. Qual o valor de m?
a) 3
b) -3
c) -1
d) 1/3
e) -1/3

Answer 1

$mx+b\\ \\ m(-2)+b=3\\ m(4)+b=1\\ \\ -2m+b=3\quad (-1)\\ 4m+b=1\\ \\ 2m-b=-3\\ 4m+b=1\\ \\ 6m=-2\\ \\ m=\frac { -2 }{ 6 } \\ \\ m=\frac { -1 }{ 3 }$

R:E