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24 votes
24 votes
If f(x) = 3x + 4, find f(–4).

User Christian Hayter
by
2.5k points

2 Answers

22 votes
22 votes

Answer:

f(-4) = -8

Explanation:

Another way you can look at it is this way.

y = 3x+4; where x = -4. In this way, you just need to find what y is.

Since we are given x, all we have to do is replace x with it's numeric value (-4).


y = 3x+4;\\y=3(-4)+4\\y=-12+4\\y=-8

Or in the same format they gave:


f(-4) = 3x+4\\f(-4) = 3(-4)+4\\f(-4) = -12 + 4\\f(-4) = -8

In the format they gave, they said what is the function of -4.

f(-4) = -8

User Muhammad Mahmoud
by
2.7k points
25 votes
25 votes

Answer:

-8

Explanation:

f(-4)= 3x+4

f(4)= 3(-4)+4

f(-4)=-12+4

f(-4)=-8

User Toon Krijthe
by
2.8k points