# Thread: Finding the Image of a point

1. ## Finding the Image of a point

Hi i need help with the following question:

The point(1,4) is on the graph of y= f(x). Determine the coordinates of the image of this point on the graph of y=3f[-4(x+1)]-2.

What i tried was plunging in 4 for y and 1 for x and solving for the image but i did not get the correct answer which is (-5,10) from my book.

Edit: what does it mean by "image" ?

2. ## Re: Finding the Image of a point

sure it's not $\left(-\frac{5}{4} , 10\right)$ ?

3. ## Re: Finding the Image of a point

can you tell me what you did and how you did it please! because this is what i got 4=3f(-8)-2 and im kind of stuck there

4. ## Re: Finding the Image of a point

"(1, 4) is on the graph of y= f(x)" means that f(1)= 4. In order to use "f(1)= 4", to calculate $3f(-4(x+1))- 2$, we must have $-4(x+1)= 1$ which is the same as x= -5/4. And then, $3f(-4(x+1)- 2= 3f(1)- 2= 3(4)- 2= 10$.

5. ## Re: Finding the Image of a point

Oh okay I understand now, thank you so much because I'm pretty sure this is going to be on my math test!