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Trigonometry-basics/369832: Find the angle θ. (Use either the Law of Sines or the Law of Cosines, as appropriate.) (Round your answer to one decimal place.)
a = 14, b = 3, c = 15
θ = ? 1 solutions
Answer 263531 by solver91311(16872) on 2010-11-11 19:08:35 (Show Source):
You can put this solution on YOUR website!
Can't help you. You don't relate in any way to the quantities , , and . Even presuming that , , and are the measures of three sides of a triangle, you don't bother to share whether is opposite side , , or -- or even whether is actually an angle in that triangle. You are apparently forgetting that this is Algebra.com, NOT the Psychic Hot Line.
John

My calculator said it, I believe it, that settles it
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Numbers_Word_Problems/369029: unit digit of 2 digit number is 6 more than it's ten's digit.if reverse the digit we find 54 more than original number.find the original number. 1 solutions
Answer 262989 by solver91311(16872) on 2010-11-10 11:33:54 (Show Source):
You can put this solution on YOUR website!
Let represent the 10s digit of the original number. Let represent the units digit of the original number. The original number is then , the number with the digits reversed is , and the digits are related by .
If reversing the digits increases the number by 54, then we can say:
Since we know that , we can substitute:
Which results in the triviality:
Ordinarily when solving a system of equations such a result would indicate that the system was consistent and dependent, which is to say that the solution set has an infinite number of elements. However, in this problem our variables are restricted to the set of single digit positive integers, namely
The smallest value can assume is 1 which implies that would be 7 and the original number would be 17. could also be 2, 8, and the original number 28, or could be 3, 9, and the original number 39. This exhausts the possibilities.
Verification that each of the three results above fit the parameters given in the problem is left as an exercise for the student.
John

My calculator said it, I believe it, that settles it
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Linear-systems/368860: As a restaurant owner there are many decisions that you need to make on a daily basis, such as where to keep inventory levels. You wish to replenish your stock of dishes by purchasing 250 sets for your restaurant. You have two dish design from which to choose. One design costs $20 per set and the other $45 per set. If you only have $6,800 to spend, how many of each design should you order?
Please help me solve this question 1 solutions
Answer 262808 by solver91311(16872) on 2010-11-09 22:48:51 (Show Source):
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Money_Word_Problems/368601: Here is my problem that I am stuck with and do not know how to finish: The problem is on Systems of Linear Equations; Matrices. The problem is: As the restaurant owern there are many decisions that you need to make on a daily basis, such as wher to keep inventory levels. You wish to replenish our stock of dishes by purchasing 250 sets for your restaurant. You have two dish design from which to choose. One design costs $20 per set and the other $45 per set. If you only have $6,800 to spend, how many of each design should you offer
Hint: Let x = the number of sets of $20 dishes and y = the number of sets of $45 dishes. Solve the equations for the different dish designs to be ordered with the desired technique: graphing, substitution, elimination matrix. Explain how to check your solution for both equations. This is as far as I got because I really don't understand it. x = $20, y = $45, total of 250, x + y = 250, $20x + 45y = $6,800 My email address is nifty_at_fifty57@yahoo.com Thank you 1 solutions
Answer 262656 by solver91311(16872) on 2010-11-09 17:09:37 (Show Source):
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logarithm/368568: you invest P dollars in an account that compounds monthly. how long will it take for the account to double to 2P dollars if the annual interest rate is the following. solve using logarithms.
2%
1 solutions
Answer 262647 by solver91311(16872) on 2010-11-09 16:43:44 (Show Source):
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Geometry_proofs/368569: how do you solve a two column proof that says the following: Given: segment AB is congruent to segment ED, segment CA is congruent to segment CE, and segment AC bisects segment BD; prove that triangle ABC is congruent to triangle EDC? I really do not understand these proofs at ALL. 1 solutions
Answer 262640 by solver91311(16872) on 2010-11-09 16:24:53 (Show Source):
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Expressions-with-variables/368567: The fixed costs of manufacturing basketballs in a factory
are $1,400.00 per day. The variable costs are $5.25 per
basketball. Which of the following expressions can be
used to model the cost of manufacturing b basketballs in
1 day? 1 solutions
Answer 262638 by solver91311(16872) on 2010-11-09 16:22:22 (Show Source):
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Linear_Algebra/368541: Hello,
Can someone please help me to solve this equation to create an equation table using x, y,(x,y).
y=-1/2x-4 (the "/" symbol represents 1 over 2)
1 solutions
Answer 262634 by solver91311(16872) on 2010-11-09 16:20:04 (Show Source):
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Probability-and-statistics/368252: An instructor gives his class a set of 17 problems with the information that the next quiz will consist of a random selection of 6 of them. If a student has figured out how to do 13 of the problems, what is the probability the he or she will answer correctly
(a) all 6 problems? 1 solutions
Answer 262409 by solver91311(16872) on 2010-11-09 00:44:13 (Show Source):
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Matrices-and-determiminant/368234: I need help with this problem please. I did row-1---row-2 then 2row-2----r2 then 3r1 + r3--r3 and I am stuck....Any help plssssss.. Thanks
Use elementary row operations to solve the linear system
X – y + 3z = 4
X + 2y – 2z = 10
3x – y + 5z = 14
1 solutions
Answer 262402 by solver91311(16872) on 2010-11-08 23:36:04 (Show Source):
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Graphs/367941: Graph the quadratic function . State the ordered pairs representing the x-intercept(s), y-intercept (if any), and the vertex of the parabola. If the parabola has a maximum or minimum, give its coordinates.
So far I have the following:
To find the y-intercept set x=0 and solve for f(x)



y-intercept is at (0,5)
To find the x-intercept set x=0 and solve for x



and then I get stuck...is this even right to this point? How do I finish this problem and how do I graph it? Also, how do I know if the parabola has a maximum or minimum and give its coordinates? 1 solutions
Answer 262267 by solver91311(16872) on 2010-11-08 17:24:10 (Show Source):
You can put this solution on YOUR website!
Use the quadratic formula where
, , and
Roughly
or
For any quadratic function of the form:
The -coordinate of the -intercept is
hence the graph intercepts the -axis at
If
is a pair of real numbers (which is true if and only if ), then the graph intercepts the -axis at
and
If
is NOT a pair of real numbers (which is true if and only if ), then the graph does not intercept the -axis at all.
The -coordinate of the vertex is
The -coordinate of the vertex is
If the lead coefficient is positive, that is if , then the parabola opens upward and the vertex is a minimum. If the lead coefficient is negative, that is if , then the parabola opens downward and the vertex is a maximum.
Finally, the axis of symmetry is the vertical line:
John

My calculator said it, I believe it, that settles it
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Probability-and-statistics/367943: We're just getting into statistics and my teacher is very helpful, but I'm still having a bit of trouble understanding how to set up a probability question for this problem: "Probability and Odds for Drawing a Card - For the experiment of drawing a single card from a standard 52-card deck, find (a) the probability, and (b) the odds in favor, of each event."
The specific question I'm asking about is the probability and odds of drawing a "Spade or Face Card." I'm not wanting someone do just do it for me, but rather show how to write it to solve, ex: P(Spade or Face card), and kind of explain it from there (what to do with the variables in the parenthesis, etc).
Thank you! 1 solutions
Answer 262247 by solver91311(16872) on 2010-11-08 16:43:17 (Show Source):
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