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.
Answer:
L = 2w
A = L*W
A = 2w*w
A = 2w^2
Step-by-step explanation:
Answer: it’s the third one
Step-by-step explanation:
It is
The percent change would be 36%
<h3>What is percent change?</h3>
Percent increase and percent decrease are measures of percent change, which is the extent to which a variable gains or loses intensity, magnitude, extent, or value.
Given:
4 candy bars = 5$
1 candy bar = 5/4
1 candy bar = 1.25$
Now,
5 candy bars = 4$
1 candy bar =4/5
1 candy bar = 0.8$
% change = (0.8-1.25) / 1.25 *100
= 36%
Learn more about percent change here:
brainly.com/question/9144026
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3 is less than or equal to x-9 is less than or equal to.
3<= x-9<=8
<= these mean less than or equal to.
hope I helped you!