Answer:
7.86 km
Step-by-step explanation:
Let x represent the distance point P lies east of the refinery. (We assume this direction is downriver from the refinery.)
The cost of laying pipe to P from the refinery (in millions of $) will be ...
0.5√(1² +x²)
The cost of laying pipe under the river from P to the storage facility will be ...
1.0√(2² +(9-x)²) = √(85 -18x +x²)
We want to minimize the total cost c. That total cost is ...
c = 0.5√(x² +1) +√(x² -18x +85)
The minimum value is best found using technology. (Differentiating c with respect to x results in a messy radical equation that has no algebraic solution.) A graphing calculator shows it to be at about x ≈ 7.86 km.
Point P should be located about 7.86 km downriver from the refinery.
Answer:
Step-by-step explanation:
<u>Given points:</u>
The perpendicular bisector passes through the midpoint.
<u>Finding the coordinates of the midpoint first:</u>
- x = (-2 + 6)/2 = 2, y = (-2 + 0)/2 = -1
<u>Next finding the slope of AB:</u>
- m = (0 - (-2))/(6 - (-2)) = 2/8 = 1/4
The perpendicular lines have negative-reciprocal slopes.
<u>The line will have a slope of -4 and pass through the point (2, -1)</u>
- y - (-1) = -4(x - 2)
- y + 1 = -4(x - 2) - point-slope form
- y = -4x + 7 - slope-intercept form
Answer:
see attached image
Step-by-step explanation: