Answer:
The speed in still water is 5 miles per hour.
Step-by-step explanation:
distance with current = 90 miles
distance against current = 10 miles
speed in still water = s
speed of current = 4 mph
speed with current = s + 4
speed against current = s - 4
time = t
speed = distance/time
distance = speed * time
With current:
90 = (s + 4) * t
Against the current:
10 = (s - 4) * t
We have a system of equations:
90 = (s + 4) * t
10 = (s - 4) * t
90 = ts + 4t
10 = ts - 4t
Subtract the second equation from the first equation.
80 = 8t
10 = t
t = 10
10 = t(s - 4)
10 = 10(s - 4)
1 = s - 4
s = 5
Answer: The speed in still water is 5 miles per hour.
This is in slope intercept form, or y=mx+b where m is slope.
m=10 in the given equation
Final answer: D
Answer:
Choice C is correct
Step-by-step explanation:
The first step is to re-write the equations in exponential form.
The first equation can be written as;
since the base is 10 and 4 the exponent.
The second equation can be written as;
The second step is to make N the subject of the formula in both equations.
Solving for N from this equation , yields;
Solving for N from the second equation , yields;
Therefore;
N; n+1; n+2 - 3 consecutive numbers
n(n + 1) = (n + 2)² - 19 |use a(b + c) = ab + ac and (a + b)² = a² + 2ab + b²
n² + n = n² + 4n + 4 - 19 |subtract n² from both sides
n = 4n - 15 |subtract 4n from both sides
-3n = -15 |divide both sides by (-3)
n = 5
n + 1 = 5 + 1 = 6
n + 2 = 5 + 2 = 7
Answer: 5; 6; 7.
Answer:
y= 
Step-by-step explanation:
2x+3y=C
isolate y
3y=C-2x
y=
