Question

Find the equation of the linear function f using the given info:

f(0)=-3, f(3)=-3

I got a slope of -3, plugged in and got y = x - 3. Is this correct?

Answer 1

How did you get slope = -3?

Answer 2

Somebody told me "since both y values are the same, evidently it is a constant, namely f(x)=−3" and to plug that in

Answer 3

But that's not how you find the slope. You find the slope by using the slope formula: (y2-y1/x2-x1)

Do you see where y2, y1, x2, and x1 are? Those are your two sets of coordinates. Use them to find the slope, then you can plug it into the y = mx + b and find b, which will give you everything you need for your equation.

Answer 4

OH, so y = 2x + b and now put in x and y from either set of points

Answer 5

I plugged in 0,0... got 0 = 2(0) + b

Answer 6

What slope did you get? Show me your calculations for slope.

Answer 7

4 - 0 = 4
-2 - 0 = -2

-4/2 = -2/1

which equals -2. My bad

Answer 8

I still get b = 0 regardless, so y = -2x + 0?

Answer 9

Where did you get 4 and 2 from? Your functions are f(0)=-3 and f(3)=-3.

Answer 10

So in the first one, x = 0, y = -3. And in the second one x = 3, y = -3. Those are your y2, x2, y1, x1.

Answer 11

Oh crap I'm sorry, was looking down at my book at the question right below the one I'm going over. it was f(0)=0, f(-2)=4. Well, got that one right now lol.

Answer 12

Doing the right one now

Answer 13

-3 + 3 = 0
3 - 0 = 3

0/3?

Answer 14

So what is your slope? Any fraction with 0 as the numerator equals what?

Answer 15

undefined?

Answer 16

No, that's if there's a 0 in the denominator. 0/3 is a number. A 0 in the numerator of any fraction just makes the fraction equal to 0.