How do you evaluate the function #f(x) = 3x+7# for #f(-5)#?

1 Answer
KillerBunny
Nov 2, 2015

#f(5)=22#.

Explanation:

To evaluate a function in a specific point, you just need to substitute every occurrence of #x# with that specific value.

In fact, #f(x)=3x+7# means "take a number #x#, triple it, and then add five". So, if our number is #5#, we must compute three times #5# and then add seven, which is exactly what happens if we do the substitution:

#f(5)=3*5+7=15+7=22#

Related questions
See all questions in Function Notation
Impact of this question
3974 views around the world
You can reuse this answer
Creative Commons License