Question

find f(10) when f(x)= -2x+9

Answer 1

-11 right?

Answer 2

f(x) = -2x + 9

f(10) = -2(10) + 9 ... replace every x with 10

f(10) = -20 + 9

f(10) = -11

So you are 100% correct

Answer 3

ok, how about this one...

Answer 4

find f(-x) when f(x) =4x+3

Answer 5

-4x-3?

Answer 6

it has to be written into an equation

Answer 7

no, f(10) means you replace every x with 10 in f(x)

f(-x) means you replace every 'x' with '-x'

Answer 8

but how do i write it into an equation

Answer 9

f(x) =4x+3

f(-x) =4(-x)+3 ... replace every x with -x

and simplify

Answer 10

so would it be -4x+3?

Answer 11

i understand the replacing.. but the equation, i JUST replace and write it as -4x+3?

Answer 12

yep

Answer 13

you got it

Answer 14

f(-x) = -4x + 3

Answer 15

ok,,, thank u! :)

Answer 16

np