Let x be the number of months.
The first plan is 15 dollars sign up fee and 38 dollars per month. So the equation is 38x + 15.
The second plan is 78 dollars as sign up fee and 31 dollars per month. So the equation is 31x + 78.
We need find when x has the same value in both equations, so we do their equality:
38x + 15 = 31x + 78
Let's subtract 15 from both sides
38x + 15 = 31x + 78
38x + 15 - 15 = 31x + 78 - 15
38x = 31x + 63
Now let's subtract 31x from both sides to have the variables on a side and the numbers on side:
38x = 31x + 63
38x - 31x = 31x - 31x + 63
7x = 63
Divide both sides by 7 to have the variable x on a side and its value on the other:
(7x)/7 = 63/7
x = 9
So at month 9, the 2 plans will cost the same.
Let's check our answers, and let y be the cost:
y = 38x + 15 = 38*9 + 15 = 357
y = 31x + 78 = 31*9 + 78 = 357
Our answer has been approved.
Hope this helps! :D
Answer:
0.607, 6.07, 60.7, 607
Step-by-step explanation:
<span>∫[(secx)−1<span>]<span>(1/2)</span></span>dx?</span> or <span>∫[sec(x−1)<span>]<span>(1/2)</span></span>dx hope it works</span>
Answer:
(b) -4.5
Step-by-step explanation:
Choosing the correct answer here is not the same as knowing what the correct value is.
<h3>Estimate</h3>
You know that √30 < √100 = 10, so the sum must be negative. That is, 10 subtracted from a positive number less than 10 will give a negative result.
You know that 25 < 30 < 36, so √25 < √30 <√36. That is, √30 will be between 5 and 6. If we say √30 ≈ 5.5, then the sum is ...
-10 +√30 ≈ -10 +5.5 = -4.5
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<em>Additional comment</em>
Of course, a calculator can tell you the value to the desired precision.