I need help with Algebra 2 work! The subject is functions.?

Question

If f(x) = 4x - 6, what is f(-3)?

6
-49
-18
-6


If f(x) = 2x and g(x) = x-4, what is the value of f[g(3)]?

-6
-2
0
6
2






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If f(x) = 2x + 3 and g(x) = (x - 3)/2, what is the value of f[g(-5)]?

-4
-10
-7
-5



If f(x) = 5x - 7, what is f -1(x)?

f -1(x)= (x+7)/5
f -1(x)=(y-7)/5
f -1(x)=5x - 7
f -1(x)=7x-5

Answer 1

-18
-2
-5

Answer 2

f(x) = 4x - 6, what is f(-3)?
f(-3) = 4(-3) - 6 = - 18

f(x) = 2x and g(x) = x-4
g(3) = 3-4 = -1
f(-1) = 2(-1) = - 2

If f(x) = 2x + 3 and g(x) = (x - 3)/2, what is the value of f[g(-5)]?
g(-5) = (x - 3)/2 = (-5-3)/2 = -4
f[g(-5)] = f(-4) = 2x + 3 = 2(-4) + 3 = - 5

If f(x) = 5x - 7, what is f -1(x)?
f -1(x) = -5x + 7

Answer 3

I'll take the 2nd one:
f(g(x)) = 2 (x-4) [see how did that?]
f(g(3)) = 2 (3-4)
= 2 (-1)
= -2

3rd one:
f(g(x)) = 2 ((x-3)/2) + 3
f(g(-5)) = 2 ((-5-3)/2)+3
f(g(-5)) = 2(-4)+3
= -5

The last one.... is the negative one an exponent?
If that's the case, think of the function as y = 5x-7
now flip flop the variables:
x = 5y-7
and solve for y again:
x+7=5y

y = (x+7)/5

See your answer now?
(10 pts, please)

Answer 4

In the first equation, substitute x with -3. so 4(-3)-6. solve.

in the second...since its f(g(x)), solve for g first.
g=3-4=-1 substitute -1 into f
f=2(-1) = -2

number 3 is the same number 2

im assuming thats inverse f in the last one...but i dont remember how to do that one :)

Answer 5

-18
-2
-5
?

Answer 6

This is algebra II? I hate to see algebra I.