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p=6x+4y, and where does it occur? 1 solutions
Answer 388070 by solver91311(17074) on 2012-06-01 18:29:31 (Show Source):
You can put this solution on YOUR website!
Substitute the coordinate values for each of your feasible region vertices and calculate the value of the objective function for each one. The largest one is the maximum of the objective. If two adjacent points have the same objective function value, then any point on the segment that joins those two points is an optimum.
John

My calculator said it, I believe it, that settles it
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Quadratic-relations-and-conic-sections/616987: All of the questions are based on the same ellipse...
1)An ellpise has foci at (-5,0)and (5,0). What is the value of c²?
2)If the sum of the focal radii of this ellpise is 12, what is the value of a²?
3)Using your conclusions, what is the value of b²?
4)What is the equation of the ellipes?
5)What are the x-intercepts of the ellipse?
6)What are the y-intercepts of this ellipse?
7) Graph the ellipse and plot the foci on a graph.
1 solutions
Answer 388069 by solver91311(17074) on 2012-06-01 18:23:04 (Show Source):
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Geometry_Word_Problems/616959: a photographer has 2 photos, each with same area. One is a square, the other a rectangle. If the length of the rectangle is 3 inches greater and the width is 2 inches shorter than the length of one side of the square, what are the dimensions of each photo?
1 solutions
Answer 388063 by solver91311(17074) on 2012-06-01 17:56:35 (Show Source):
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Numeric_Fractions/616970: Can you please give me the answer to this equation, and explain how the answer was derived?
If 5x + x² > 100, then x is not
Thank you. 1 solutions
Answer 388044 by solver91311(17074) on 2012-06-01 17:00:14 (Show Source):
You can put this solution on YOUR website!
It is impossible to do what you ask. You can't solve an equation that doesn't exist. What you have provided is an inequality, NOT an equation. On the other hand, you need to turn it into an equation in order to determine the solution set interval.
Step 1: Replace the inequality sign with an equals sign.
Step 2: Put the equation into standard quadratic form.
Step 3: Evaluate the discriminant, i.e., , to determine that the quadratic does not factor over the rationals.
Step 4: Use the quadratic equation to find the conjugate pair of irrational roots of the equation.
Step 5: Divide the -axis into three regions, up to the smaller value root, the smaller value root to the larger value root, and the larger value root to .
Step 6: Select any one of the three intervals, and select a value from that interval that is NOT an endpoint value. Substitute this value into the original inequality and do the arithmetic.
Step 7: If the result of step 6 is a true statement, then the interval selected is contained in the solution set of the inequality. Otherwise not.
Step 8: Repeat steps 6 and 7 for each of the other intervals.
Use the results to fully describe the solution set. Generally, interval notation is best.
John

My calculator said it, I believe it, that settles it
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Mixture_Word_Problems/616946: A new lab technician, on his first day on the job, drops his lab key into a large bottle of concentrated nitric acid, and key begins to dissolve. the mass of the key is 2.03 oz (1 oz=28.35g) and has a density of 6.347 g/cm^3. The acid dissolves the key at a rate of 0.00235 g/s. By the time the lab tech gets the key out of acid, 10.0 minutes have passed.What is the volume of the key by then?
I solved this
then but I feel like the answer is wrong. 1 solutions
Answer 388034 by solver91311(17074) on 2012-06-01 16:38:46 (Show Source):
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Miscellaneous_Word_Problems/616950: John rents a booth for $35.00 a day and sells ice cream cones.
His cost for each cone is $2.00 and he sells the cones for $5.00 each.
If John wants to make at least a $200.00 profit for the day, how many ice cream cones must he sell?
a. 34
b. 78
c. 79
d. 118
Which would be the correct answer and please explain, the way to arrive at the answer... please.. 1 solutions
Answer 388022 by solver91311(17074) on 2012-06-01 15:26:46 (Show Source):
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Trigonometry-basics/616932: 1. Complete the last step to prove the following identity. Express answer in terms of sin and/or cos only.
cot B sec B=csc B
2. Change this problem to an expression of sin and/or cos only.
tan A - sec A =
3. Complete the last step to prove the following identity. Express answer in terms of tangent and/or cotangent only.
(1+tan^(2)x)/(tan^(2)x)=csc^(2)x 1 solutions
Answer 388014 by solver91311(17074) on 2012-06-01 12:43:34 (Show Source):
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Triangles/616924: if one leg of a 30, 60 ,90 degree triangle has a length of 6 and the adjacent angel is 30 , what is the exact length of the hypotenuse in simplest radical form 1 solutions
Answer 388006 by solver91311(17074) on 2012-06-01 12:28:03 (Show Source):
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Rectangles/616703: Question: Determine the dimension of a rectangle with a perimeter of 40cm and the greatest possible area.
Book's answer is: 10cm by 10cm
I do not get how can you get 10cm by 10cm, if it is a rectangle.
Please help me! Thank you. 1 solutions
Answer 387847 by solver91311(17074) on 2012-05-31 17:34:23 (Show Source):
You can put this solution on YOUR website!
A square is just a special case of a rectangle. There is nothing wrong with calling a square a rectangle any more than it is wrong to call a square a rhombus, parallelogram, or just a plain old quadrilateral.
Having said that, given a rectangle with length , width , perimeter , and area , we can first describe the length in terms of the width and the perimeter:
Substituting this into the area formula, we create a function for area in terms of width:
Rearranging in to standard quadratic form:
Recognizing that this second degree polynomial function in graphs to a parabola, opening downward because of the negative lead coefficient, that must have a vertex as a maximum function value.
Using the fact that has a vertex at , we can find the vertex of our function:
This means that the maximum of the function, that is to say the maximum area rectangle for any given perimeter is a rectangle with a width one-fourth of the perimeter. If the width is one-fourth, two times the width has to be one-half of the perimeter, leaving one-half of the perimeter to account for two times the length, hence the length must also be one-fourth of the perimeter.
John

My calculator said it, I believe it, that settles it
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Linear-equations/616676: Find the equation of the line that passes through the points (–4, -1) parallel to 6x-y=6 1 solutions
Answer 387844 by solver91311(17074) on 2012-05-31 17:13:14 (Show Source):
You can put this solution on YOUR website!
You cannot find "the" equation of any line. You can only write "an" equation of a line. In the first place, you could just substitute the values in the point-slope form and have an equation of the desired line, or you could solve for to put it into slope-intercept form, or you could rearrange it into standard form, namely . Furthermore, for a given , , and , where describes a set of equations with an infinite number of elements, each of which graphs to the same line in .
First put your given equation into slope intercept form. Make sure that the coefficient on is reduced to lowest terms if necessary. Then, by inspection of the coefficient on you can determine the slope of the given line.
Parallel lines have equal slopes. Use the point-slope form of an equation of a line, the given point and the slope determined as described to write an equation of your desired line.
where are the coordinates of the given point and is the given/calculated slope.
Follow your instructor's or textbook's instructions as to form of your answer.
John

My calculator said it, I believe it, that settles it
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