Answer:
y=-4x-6
Step-by-step explanation:
y=mx+b, where m is the slope and b is the y-intercept
Slope is given as -4, so:
y=-4x+b
To find b, sub in the point we were given (-2,2):
2=-4(-2)+b
2=8+b
b=2-8=-6
So we have: y=-4x-6
Answer:
I believe it’s C but not 100% sure
Step-by-step explanation:
Answer:
P is exactly 3km east from the oil refinery.
Step-by-step explanation:
Let's d be the distance in km from the oil refinery to point P. So the horizontal distance from P to the storage is 3 - d and the vertical distance is 2. Hence the diagonal distance is:

So the cost of laying pipe under water with this distance is

And the cost of laying pipe over land from the refinery to point P is 400000d. Hence the total cost:

We can find the minimum value of this by taking the 1st derivative and set it to 0

We can move the first term over to the right hand side and divide both sides by 400000


From here we can square up both sides






d = 3
So the cost of pipeline is minimum when P is exactly 3km east from the oil refinery.
The answer is c, -1 or -7
Hope this helped :)