Question

If `f(x) = 5x^2+6` and `g(x) = -3x+3`, what is `(f-g)(-3)`?

Answer 1

`39`

Explanation:

Remember that `(f-g)(x)=f(x)-g(x)`.

Here, `f(x)=5x^2+6` and `g(x)=-3x+3`.

`f(x)-g(x)=h(x)=5x^2+6-(-3x+3)`

`h(x)=5x^2+6+3x-3`

`h(x)=(f-g)(x)=5x^2+3x+3`

So, we now have `(f-g)(x)`. Next, we can do:

`(f-g)(-3)=h(-3)=5(-3)^2+3(-3)+3`

`(f-g)(-3)=39`

Our answer.

Answer 2

`(f-g)(-3)=39`

Explanation:

`(f-g)(x)=f(x)-g(x)`

`color(white)((f-g)(x))=5x^2+6-(-3x+3)`

`color(white)((f-g)(x))=5x^2+6+3x-3`

`color(white)((f-g)(x))=5x^2+3x+3`

.`"to evaluate "(f-g)(-3)" substitute x = - 3 into "(f-g)(x)`

`(f-g)(color(red)(-3))=(5xx(color(red)(-3))^2)+(3xxcolor(red)(-3))+3`

`color(white)(xxxxxxxx)=(5xx9)-9+3`

`color(white)(xxxxxxxx)=45-9+3=39`

Answer 3

39

Explanation:

we have got f(x)=`5x^2+6`
we have to find f-g..so lets find it f-g=`5x^2+6+3x-3`= `5x^2+3x+3`

now put x=-3 in above equation
we ll get result
thnx!!!