we are given that
8 more than a number is greater than or equal to 0
Let's assume that number as 'x'
8 more than a number is
now, it is greater than or equal to 0
so, we can write as
now, we can solve for x
Subtract both sides 8
...............Answer
Answer:
<h3>r = -13</h3>
Step-by-step explanation:
The formula of a slope:
We have the slope m = 2/3 and the points (-4, 3) and (r, -3). Substitute:
<em>cross multiply</em>
<em>divdide both sides by 2</em>
<em>subtract 4 from both sides</em>
Current concentration =5%
Current volume = 50 gallons
Current brine content = 0.05*(50 gallons) = 2.5 gallons.
Let x = gallons of water that evaporated.
Then
Final volume = (50 -x) gallons
Final concentration = 8%
Final brine content = 0.08*(50 - x) = 4 - 0.08x gallons
The brine content did not change, therefore
4 - 0.08x = 2.5
-0.08x = -1.5
x = 18.75 gallons
Answer: 18.75 gallons
Answer: speed of plane is 720 km/h
Speed of wind is 80km/h
Step-by-step explanation:
Let x represent the speed of the plane.
Let y represent the speed of the wind.
The plane flies from Atlanta to los Angeles and against the wind in 5hrs and the distance between Atlanta and los Angeles is 3200 km.
Since it flew against the wind, the speed would be x-y km/hour
Distance = speed × time. Therefore
3200 = 5(x - y )
3200 = 5x - 5y - - - - - - - - - 1
the return trip back to Atlanta with the wind only 4 hr. This means that the speed is x+y km/hour. Therefore
3200 = 4(x+y)
3200 = 4x + 4y - - - - - - - - 2
Multiplying equation 1 by 4 and equation 2 by 5, it becomes
12800 = 20x - 20y
16000 = 20x - 20y
Adding both equations, it becomes
28800 = 40x
x = 28800/40 = 720
Substituting x = 720 into 3200 = 5(x - y )
x - y = 3200/5 = 640
y = 720 - 640 = 80
