Answer:
480/(x+60) ≤ 7
Step-by-step explanation:
We can use the relations ...
time = distance/speed
distance = speed×time
speed = distance/time
to write the required inequality any of several ways.
Since the problem is posed in terms of time (7 hours) and an increase in speed (x), we can write the time inequality as ...
480/(60+x) ≤ 7
Multiplying this by the denominator gives us a distance inequality:
7(60+x) ≥ 480 . . . . . . at his desired speed, Neil will go no less than 480 miles in 7 hours
Or, we can write an inequality for the increase in speed directly:
480/7 -60 ≤ x . . . . . . x is at least the difference between the speed of 480 miles in 7 hours and the speed of 60 miles per hour
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Any of the above inequalities will give the desired value of x.
Equation 1) x + 6y = 2
Equation 2) 5x + 4y = 36
Multiply all of equation 1 by 5.
1) 5(x + 6y = 2)
Simplify.
1) 5x + 30y = 10
2) 5x + 4y = 36
Subtract equations from one another.
26y = -26
Divide both sides by 26.
y = -1
Plug in -1 for y in the first equation.
x + 6y = 2
x + 6(-1) = 2
Simplify.
x - 6 = 2
Add 6 to both sides.
x = 8
D : (8, -1)
~Hope I helped!~
