Given that the time taken to get to campus is inversely proportional to driving rate, let the time be t and rate be r, thus the function will be written as:'
t=k/r
where
k is the constant of proportionality given by:
k=tr
when r=20 mph, t=1.25 hrs
thus
k=20×1.25
k=25 miles
thus the formula is:
t=25/r
when r=55 mph, the value of t will be:
t=25/55
t=5/11 hours
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Define x :
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Let Cheryl be x years old.
Cheryl = x
Lisa = x + 6
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In two years time:
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Cheryl = x + 2
Lisa = x + 8
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Lisa will be twice as old as Cheryl :
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x + 8 = 2(x + 2)
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Solve x :
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x + 8 = 2(x + 2)
x + 8 = 2x + 4
x = 4
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Find their age :
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Cheryl = x = 4
Lisa = x + 6 = 4 + 6 = 10
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Answer: Lisa is 10 years old now.
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Answer:
-2 and -7
Step-by-step explanation:
This problem is about using the Factoring X.
Two numbers will multiply to the number placed at the top. These same two numbers will add to the value placed on the bottom.
Let's look at the factors of 14.
1 • 14 = 14
2 • 7 = 14
Now let's look at their sums.
1 + 14 = 15
2 + 7 = 9
We can see that 2 and 7 multiply to 14 and add to 9.
However, we need them to add to -9.
Note that two negative numbers multiplied will become positive.
-2 • - 7 = 14
Now let's look at their sum.
-2 + (-7)
Simplify the negative.
-2 - 7 = -9
We can see that -2 and -7 multiply to 14 and add to -9.
Hope this helps!
2x - 10 = 30
2x = 40
x = 20
Under Daily flat rate, we would have 22 and 0.15x
Under Cost per mile, we would have 0.15
Under Number of Miles Driven, we would have x