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Graphs/563115: Graph the following equation; calculate the slope, x-intercept, and y-intercept, and label the intercepts on the graph.
y = x + 3
1 solutions
Answer 364909 by richard1234(5390) on 2012-01-26 23:48:12 (Show Source):
You can put this solution on YOUR website!Slope = 1
x-intercept occurs when y = 0, i.e. 0 = x+3, x = -3. x-intercept: (-3,0)
y-intercept occurs when x = 0, y = 0+3 = 3. y-intercept: (0,3)
Graph of the function:
http://www.wolframalpha.com/input/?i=y%3Dx%2B3
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Rectangles/562968: If the area of a rectangle can be expressed as x2+x-56 cm2, what is the smallest possible value of x? Explain. 1 solutions
Answer 364908 by richard1234(5390) on 2012-01-26 23:45:45 (Show Source):
You can put this solution on YOUR website!x^2 + x - 56 = 0 when x = 7 or x = -8 (you can check by factoring). It can be shown that x^2 + x - 56 is positive when x > 7 or x < -8. Hence there is no smallest possible value of x (since x can go to negative infinity and the area is still positive). Note that the dimensions themselves do not necessarily have to be polynomials.
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Points-lines-and-rays/563238: Pre Algebra Chapter 6 Resource Book.
McDougal Littell
Lesson 6.5 Practice A
for use with pages 293-297
How to find the specified side length...Given ABC - JKL, find JL
Thank you. 1 solutions
Answer 364907 by richard1234(5390) on 2012-01-26 23:42:04 (Show Source):
You can put this solution on YOUR website!Surely you don't expect tutors on algebra.com to own the exact same textbook that you are using. You should explain the problem more in depth.
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test/563151: Let A, B, C, be integers such that is an integer. Prove that , , are integers. 1 solutions
Answer 364904 by richard1234(5390) on 2012-01-26 23:37:41 (Show Source):
You can put this solution on YOUR website!You can let  where k is an integer, then  . Cubing both sides,
Here, we can take this equation "modulo 1" by eliminating all the integer expressions (b,c,k^3,3ka).
Factor LHS
 \equiv -3k^2\sqrt{a} - a\sqrt{a} (mod 1)) Note that you can replace  with  . Modulo 1, this is equivalent to -sqrt(a).
Here, we show that ) i.e. it is an integer. I'll let you finish the proof that sqrt{a}, sqrt[3]{b}, and sqrt[3]{c} have to be integers. Pretty daunting problem...unfortunately we cannot assume the converse of the statement is true (i.e. if ... are integers then ... is an integer).
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Geometry_proofs/563454: a) Prove the diagonals of a cyclic quadrilateral bisect each other
b) prove if the diagonals of a quadrilateral bisect each other then the quadrilateral is cyclic.
I know the opposite sides of the quadrilateral are equal and the SAS theorem proves the triangles made by the diagonals are equal I just dont know how to write the proofs 1 solutions
Answer 364901 by richard1234(5390) on 2012-01-26 23:26:58 (Show Source):
You can put this solution on YOUR website!Statements a) and b) cannot be true, since it is possible to find counterexamples for each one. Note that a cyclic quadrilateral is a quadrilateral whose four vertices all lie on a circle.
For statement a), a "kite" shape formed by taking a right triangle and reflecting it about the hypotenuse is a counterexample, since such a quadrilateral is cyclic and not every kite shape will have diagonals that bisect each other.
For statement b), a parallelogram (other than a rectangle) is a counterexample, because its diagonals bisect each other, but parallelograms (other than rectangles) *cannot* be cyclic (since opposite angles must add to 180).
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Angles/563441: The ratio of the measures of two complimentary angles is 11:5. Find the measures of the angles. 1 solutions
Answer 364881 by richard1234(5390) on 2012-01-26 22:10:09 (Show Source):
You can put this solution on YOUR website!"Complementary," not "complimentary."
Let 11x and 5x be the angles. Since they're complementary, their sum is 90, so 11x+5x = 90. Solve for x, then find 11x and 5x.
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Probability-and-statistics/563426: What is the variance and the standard deviation of the scores 51,55,61,62,68,71,71,73,81,82,87,89,92,94,95,100?
Can someone please help and show all work?
Thanks 1 solutions
Answer 364879 by richard1234(5390) on 2012-01-26 22:01:25 (Show Source):
You can put this solution on YOUR website!Note that
and that variance is equal to the square of the standard deviation. The best method is simply to use a calculator to input the data values, and you should obtain
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logarithm/563456: I need help solving for x in this logrithm:
Log(11x + 9) = 3 + log(x + 3)
First I moved both logs to the same side:
Log(11x + 9) - log(x + 3) = 3
Then I divided the logs in order to condense the equation:
Log (11x + 9)/(x + 3) = 3
Next I switched the equation from log form to expodential form:
10^3 = (11x + 9)/(x + 3)
Then I distributed the exponent to the 10 and multiplied (x + 3) to both sides:
1,000(x + 3) =(11x +9)
1,000x + 3,000 = 11x + 9
Then I put the x's on the same side & all whole numbers:
989x = -2991
Then I divided to find x:
X = -2991/989; x = -3.024266936.
Now I realize I did something wrong to come up with this answer so could you please help me? 1 solutions
Answer 364878 by richard1234(5390) on 2012-01-26 21:55:18 (Show Source):
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logarithm/562946: In a logarithm, why would you let it equal 1, for example, log(8)4=1 , rather than having it equal 1/2 ?
I just want to understand logarithms a little bit more. Thank you 1 solutions
Answer 364797 by richard1234(5390) on 2012-01-26 16:17:17 (Show Source):
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real-numbers/563024: 1. What is the difference between natural numbers and rational numbers?
2. What is the difference between rational numbers and real numbers?
3. What is the difference between whole numbers and integers?
4. Why is there a rule that says x^0=1?
5. Why is there a rule that says 5/0 = undefined? 1 solutions
Answer 364794 by richard1234(5390) on 2012-01-26 16:14:41 (Show Source):
You can put this solution on YOUR website!For #1-3, review what natural numbers, rational numbers, integers, etc. are defined as.
For #4, x^0 = 1 because x^(a-b) = (x^a)(x^b), so if a = b, x^0 = (x^a)/(x^a) = 1 (assume x is not 0).
For #5, 5/0 is undefined because we cannot divide 5 into groups of zero.
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Parallelograms/563081: Can u tell me the formulae for finding area of parallelogram with 4 coordinates? 1 solutions
Answer 364791 by richard1234(5390) on 2012-01-26 16:12:01 (Show Source):
You can put this solution on YOUR website!Suppose the coordinates are (0,0), (a,b), (c,d) and (a+c,b+d) (we may assume one of the coordinates is (0,0) in order to fix a point). Then the area is equal to the determinant of the matrix
|a b|
|c d|
or ad-bc.
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Numbers_Word_Problems/561896: What number is the sum of 17 times its first digit, 34 times its second digit, and 51 times its third digit? Why? 1 solutions
Answer 364490 by richard1234(5390) on 2012-01-24 22:22:32 (Show Source):
You can put this solution on YOUR website!If a,b,c denote the digits, then
 (right away we know the number is a multiple of 17)
Here, we conclude that a is even (since RHS is even). Now consider the equation mod 10 (if you don't know modular arithmetic, think of it as "matching the units digits on LHS and RHS").
If a = 2, then b = 4 or 9, but neither allows for an integer value of c. If a = 4, then b = 3 or 8, but likewise, there are no integer solutions for c. If a = 6, then b = 2 or 7, and it can be checked that b = 2 allows for the number 629. If a = 8, then b = 1 or 6, but neither allows for integer solutions.
Hence the only number is 629.
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Functions/562038: 
Find g(x)+5
I'm not sure how to go about finding the value of g(x)+5 since there is still a variable and the +5 is on the outside of the parenthesis, but on the left side of the "equation." 1 solutions
Answer 364483 by richard1234(5390) on 2012-01-24 22:07:49 (Show Source):
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