Answer:
$4779
Step-by-step explanation:
First you need to write an equation to model this situation. In this case it's f(x)=1000(1.12)^x. College usually lasts 4 years, so to find the total amount of money they need to budget, you need to find the sum of f(0), f(1), f(2), and f(3).
This is roughly equivalent to 1000+1120+1254+1405, which equals 4779.
<h3>
Answer: C) x = 80</h3>
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Work Shown:
Let's cross multiply to get the following
14/20 = 56/x
14*x = 20*56
14x = 1120
x = 1120/14
x = 80
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As a way to check the answer, we can type 14/20 - 56/80 into the calculator and we should get 0. I'm taking advantage of the rule that if A = B, then A-B = 0. This trick is handy to check if two sides of any equation are equal to one another.
Answer:
x=(0.45,-4.45)
Step-by-step explanation:
x²+4x=2
x²+4x+(2)²=2+(2)²
x²+(2)²=2+4
(x+2)²=6
√(x+2)²√6
x+2=√6
x=-2±√6
x=-2±2.45
x=(0.45,-4.45)
18 is the least common denominator of all the fractions, so you can eliminate fractions by multiplying the equation by 18.
(4.5*18)x +((7/9)*18)x + (2 1/3)*18 + ((1/6)*18)x = (5 1/18)*18
81x +14x +42 +3x = 91 . . . . . simplify
Collect terms.
98x + 42 = 91
98x = 49 . . . . . . . . . subtract 42
x = 49/98 = 1/2
The solution is x = 1/2.
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You can also do the arithmetic with mixed numbers and fractions. The usual methods apply.
(4.5 + 7/9 + 1/6)x + 2 1/3 = 5 1/18
(49/9)x + 7/3 = 91/18
(49/9)x = 49/18 . . . . . . . subtract 7/3
x = (9/49)(49/18) = 9/18 = 1/2 . . . . . multiply by 9/49
This can be a little more tedious than the method above, but it works and it will give you the right answer. A calculator that works with fractions can make this solution as easy as the other one.
Answer:5.25
Step-by-step explanation:
(7/8 of a mile) x (6 days)