The function y=40x describes how far from home Shu Ling is as she drives from Dallas to Miami. Graph the function. Use the graph to estimate how far from home Shu Ling is in 12 hours.

You can see the graph below.

To answer the question, you need to draw a vertical line from x = 12h up, until the line meets with the line.

Once the line meets with the line, draw a horizontal line from that point, and the value where this line intersects with the y-axis will be the distance from home after 12 hours.

The graph is kinda hard to read because the line is really steep, the green line is the equation y = 40*x

the red line is a line at x = 12

The black dashed line is the horizontal line that intersects with the y-axis.

In the graph, you can see that the dashed line intersects the y-axis at around y = 475.

Then a good estimate is that the distance after 12 hours is 475 (miles).

Now, we can compare this with the direct calculation, just replace x by 12 in the given line:

y = 40*12 = 480.

So our estimation is really accurate.