Answer #1- f(x)=0x-4
Answer #2-f(x)=2/3x+4
Answer #3-Undefined
Answer #4-f(x)= -1/5x+2
Function notation means that instead of y=mx+b, your equation will be f(x)=mx+b. F(x) and y are the same thing, and are interchangeable. However, when asking for the equation in function notation, f(x)=mx+b is how the equation is to be written.
F(x)=y
M=slope
X=variable
B=y-intercept
Let’s start with the first image. To find slope, you always use for formula rise/run. Seeing as there is no movement in the graph (values are neither increasing or decreasing), the slope is 0. Let’s add that into the equation.
f(x)=0x+b
Now let’s find b. B is where the line intersects on the y-axis on the graph. Here it is-4. Let’s add that in now.
f(x)=0x-4
Let’s move onto the second image. We see that the line intersects the y-axis at 4. Let’s add that in.
f(x)=mx+4
Now let’s find the slope. We’ll look at points (-6,0) and (0,4) to find the difference going up/down over left/right. This would be 2/3. Let’s add that into the equation
f(x)=2/3x+4
Lets move onto the third image. Much like image 1, there the values here are neither increasing or decreasing. But, this line is vertical, so the slope is undefined. That would be the answer for #3
Let’s finally do number 4. The line intersects at 2, so let’s fill that in for b now.
f(x)=mx+2
The values in the graph are negative, so m will be negative as well. Let’s add that in.
f(x)=-mx+2
Let’s find slope now. Looking at points (0,2) and (10,0), I see that the difference in rise/run is 2/10. This simplifies to 1/5. Let’s add that in
f(x)= -1/5x+2
These are your answers! Hope this helps comment below for more questions :)
