If f(x) = -6x - 3, then how do you find f(2)?

2 Answers
Gió
Jul 2, 2015

f(2)=-15

Explanation:

Substitute 2 instead of x into your function so you get:
f(2)=(-6*2)-3=-12- 3=-15

Jim H
Jul 2, 2015

Replace every x with 2 and do the arithemetic.

Explanation:

In the definition of this function the variable x is a name for the blank space. (Definition for the rest of this one problem, not for other problems too.)

fcolor(red)((x)) = -6 color(red)((x)) -3

To find f(2), replace all of the x'swith 2 and do the arithmetic.

fcolor(red)((2)) = -6 color(red)((2)) -3

Now we do the arithmetic:

f(2) = -6(2) -3 = -12 - 3 = -15

Here's another example: for the same f, find f(-5)

Solution:
fcolor(red)((-5)) = -6 color(red)((-5)) -3

= 30-3
= 27

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