Question

Dada á função f(x)=ax+2, determine o valor de 'a' para que se tenha f(3)=20.

Answer 1

$f(x)=ax+2\\f(3)=3a+2=20\\\\3a+2=20\\3a=20-2\\3a=18\\\\a=\frac{18}{3}\\\\\fbox{a = 6}$

Answer 2

f(x)=ax+2

a*3+2=20

3a=20-2

3a=18

a=18/3

a=6