which residual plot shows that the line of best fit is a good model?

The first one.

Step-by-step explanation:

In the first plot, the data are grouped somewhat tightly together in a shape that resembles a line.  This means a line of best fit will work.

In the second plot, the points seem to form an arch towards the middle; a line would not be a good fit for this data.

In the third plot, the data is too scattered to draw a best fit model.

In the fourth plot, the points seem to form a u-shape towards the middle; a line would not be a good fit for this data.

let's cover over the formula of the vertex:

y = a(x – h)^2 + k

in this formula, (h,k) are the vertex, always remember that the positive or negative value of the vertex is based on the sign it has.

for example, if the vertex is -3,-6 then both the x and y value would have the positive sign attached to it and if it were a positive x and y value, then a negative sign would be attached to it.

with that being said, for our problem the x value is a positive one so we are looking for a number with a negative sign next to it, in this case the first and second choice.

however, for the first answer choice it isn't quite part of the formula so we know that the answer choice correctly displays the x value.

to confirm, we can see if the -1 fits correctly with the second answer choice, and as mentioned above a negative number will have a positive sign attached to it. so, for our problem we can see that -1 has been changed to +1, so we can confirm that the second answer choice is correct.

hence, our final answer is y=(x - 1)^2 + 1

with btw u said 100pts but it clearly says

i answerd and just got 10pts

no hate