Answer:
D
Step-by-step explanation:
Answer:

Step-by-step explanation:
A road is perpendicular to a highway leading to a farmhouse d miles away.
An automobile passes through the point of intersection with a constant speed
= r mph
Let x be the distance of automobile from the point of intersection and distance between the automobile and farmhouse is 'h' miles.
Then by Pythagoras theorem,
h² = d² + x²
By taking derivative on both the sides of the equation,




When automobile is 30 miles past the intersection,
For x = 30

Since 
Therefore,


Answer:
Think of y = mx + b,
With y = x + 3, m = 1 so the slope is one, and b = 3 which is the y-intercept, so plot the point (0,3) on the y-axis.
To find the next point to plot go up 1 and over to the right 1 because slope is rise over run.
With y = x, the slope is still 1, but there is no y-intercept, so you plot the point (0,0), and to find the next point on that line, go up 1 and over the right 1 because m=1
Used show you have more than what is needed. Example is you need 6 slices of pizza for all your friends but have 7 slices you have more than is needed.