Question

Which is the value of g(-5) if g(x)=3. 4x-8

Answer 1

I'm going to take a chance and assert that by "g(x)=3. 4x-8" you actually meant g(x)=3.4x-8.

We substitute -5 for x in g(x)=3.4x-8, obtaining g(-5)=3.4(-5)-8

= -17 - 8, or g(-5) = -25

Answer 2

I believe the answer is -25