Answer:
9 mph
Step-by-step explanation:
-let x be the speed of current and t be time. The speed equation for both directions can then be represented as:

#Since t is equal in both, we can do away with t.
#We the divide the downstream equation by the upstream equation as:

Hence, the boat's speed in still water is 9 mph
Answer:
Dimensions of the rectangular plot will be 500 ft by 750 ft.
Step-by-step explanation:
Let the length of the rectangular plot = x ft.
and the width of the plot = y ft.
Cost to fence the length at the cost $3.00 per feet = 3x
Cost to fence the width of the cost $2.00 per feet = 2y
Total cost to fence all sides of rectangular plot = 2(3x + 2y)
2(3x + 2y) = 6,000
3x + 2y = 3,000 ----------(1)
3x + 2y = 3000
2y = 3000 - 3x
y = ![\frac{1}{2}[3000-3x]](https://tex.z-dn.net/?f=%5Cfrac%7B1%7D%7B2%7D%5B3000-3x%5D)
y = 1500 - 
Now area of the rectangle A = xy square feet
A = x[
]
For maximum area 
A' =
= 0
1500 - 3x = 0
3x = 1500
x = 500 ft
From equation (1),
y = 1500 - 
y = 1500 - 750
y = 750 ft
Therefore, for the maximum area of the rectangular plot will be 500 ft × 750 ft.
two fencing 3(500+500) = $3000
other two fencing 2(750+750) = $3000
Answer:
90,000,000 + 90,000 + 10
I hope this helped!
Step-by-step explanation:
First question:
1. Set equations equal to each other so 5x-9=2x+6
2. Put x's on one side so that 3x=15
3. Divide by 3 so that x=15
4. Substitute 15 in for x so that y=2(15)+6
5. Solve for y so that y=36
6. Thus the equations intersect at (15,36)
Second question:
1. Since for lines y=mx+b, and m=slope=3 you only need to write an equation with slope 3
2. y=3x+b, b can be any number
Hello
A. will be your answer.
Hoped This Helped! :D