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all answered: 299 problems
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Angles/758970: Find the measure of an angle if its measure is 50 degrees more than the measure of its complement
1 solutions

Answer 461741 by Cromlix(718) About Me  on 2013-06-18 08:44:00 (Show Source):
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Two angles are complementary if the sum of their angles equals 90 degrees
So, one angle is 40 degrees if it is 50 degrees more than its complement.
Hope this helps.
:-)


Travel_Word_Problems/758967: If a car travels 60 km in 4 hours what speed is the car doing?
1 solutions

Answer 461740 by Cromlix(718) About Me  on 2013-06-18 08:39:52 (Show Source):
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If a car is travelling at 60km for 4 hrs
Speed = Distance/ Time
It is travelling at an average speed of 15km/hr
Hope this helps.
:-)


Triangles/758968: The measures of the angles in a triangle are in the extended ratio of 3:4:5. What is the smallest angle of the triangle?

1 solutions

Answer 461739 by Cromlix(718) About Me  on 2013-06-18 08:38:05 (Show Source):
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Add all the ratios
3+4+5 = 12
180 degrees in a triangle.
3/12 x 180 = 45
4/12 x 180 = 60
5/12 x 180 = 75
Total = 180
So, smallest angle = 45 degrees.
Hope this helps.
:-)


Linear-systems/758930: 2-3j/5=3-4j/6
1 solutions

Answer 461738 by Menjax(41) About Me  on 2013-06-18 06:25:00 (Show Source):
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If you meant 2 -(3j/5)... J=15
If you meant (2-3j)/5... J=3/2


Age_Word_Problems/758936: mark is five times older than his sister.if the sum of their ages three years ago is twenty seven. how old is mark
1 solutions

Answer 461737 by Menjax(41) About Me  on 2013-06-18 06:20:54 (Show Source):
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Let m be marks current age
Let s be his sisters current age
m=5s #1
(m-3) + (s-3) = 27 #2
From 1
5s-3+s-3=27
6s=33
s=11/2
m=55/2


test/758943:
1 solutions

Answer 461736 by Alan3354(31521) About Me  on 2013-06-18 06:18:55 (Show Source):


Equations/758939: (5*3)=(10+5)*3

1 solutions

Answer 461735 by Menjax(41) About Me  on 2013-06-18 06:16:53 (Show Source):
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This equation is untrue :)


Points-lines-and-rays/758941: THE MIDPOINT OF A LINE SEGMENT AB IS THE POINT (-1, 2).THE X COORDINATE OF A IS 5 AND THE Y-COORDINATE OF B IS -9,FIND THE POINTS OF A+B
1 solutions

Answer 461734 by Menjax(41) About Me  on 2013-06-18 06:15:11 (Show Source):
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First off please don't use caps to gain attention it's unnecessary...
using formulas
Mx=(x1+x2)/2
My=(y1+y2)/2
-1=(5+x2)/2
2=(y1-9)/2
Point A is at (5,-5)
Point B is at (-7,-9)


Age_Word_Problems/758940: Two years ago, a man was 7 times as old as his son. In 3 years time, he will be only 4 times as old as son. Find the present age of the man and of his son.
1 solutions

Answer 461733 by Menjax(41) About Me  on 2013-06-18 06:10:20 (Show Source):
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Defince unknowns
Let M = Man's current age
Let S = Son's current age
Dissect the question to get your equations
(M-2) = 7(S-2) #1
(M+3) = 4(S+3) #2
From #1 M = 7S-12
Sub above into #2
7S-9=4S+12
3S=21
S=7
Sub S into #1
M-2=7(7-2)
M=37
So the man's current age is 37 years old and his son's age is 7 years old


Quadratic_Equations/755455: +x%5E2%2B4x%2B3=0+
s.s {-3,-1}

1 solutions

Answer 461732 by GETASEW(1) About Me  on 2013-06-18 05:46:30 (Show Source):


Probability-and-statistics/758924: Not really sure where to start on this problem. Any help you can give me would be greatly appreciated.
Determine whether the distribution is a discrete probability distribution?
x,P(x)
0,0.21
1,0.28
2,0.02
3,0.28
4,0.21
1 solutions

Answer 461731 by reviewermath(604) About Me  on 2013-06-18 04:35:18 (Show Source):
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Q:
Not really sure where to start on this problem. Any help you can give me would be greatly appreciated.
Determine whether the distribution is a discrete probability distribution?
x,P(x)
0,0.21
1,0.28
2,0.02
3,0.28
4,0.21
-------------------------------------------------------------
A:
highlight%28Yes%29, the distribution is a discrete probability distribution
because sum%28P%28x%29%2C+x+=+0%2C+4%29 = 0.21 + 0.28 + 0.02 + 0.28 + 0.21 = highlight%281%29.


logarithm/758637: 2logx-2=log (x-25)
1 solutions

Answer 461730 by lwsshak3(6761) About Me  on 2013-06-18 03:13:51 (Show Source):
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2logx-2=log (x-25)
2logx-log (x-25)=2
log%28x%5E2%2F%28x-25%29%29=log%28100%29
%28x%5E2%29%2F%28x-25%29=100
x^2=100x-2500
x^2-100x+2500=0
(x-50)^2=0
x=50


Trigonometry-basics/758803: Refer to the graph of y = tan x to find the exact values of x in the interval (−π/2, 3π/2) that satisfy the equation. (Enter your answers as a comma-separated list.)
tan x = 1/square root of 3


1 solutions

Answer 461729 by lwsshak3(6761) About Me  on 2013-06-18 03:00:50 (Show Source):
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Refer to the graph of y = tan x to find the exact values of x in the interval (−π/2, 3π/2) that satisfy the equation. (Enter your answers as a comma-separated list.)
tan x = 1/square root of 3
***
x=π/6, 7π/6 in Q1 and Q3 where tan>0


Trigonometry-basics/758863: find csc(theta), given that cos(theta)=(-(√2/2)) and cot(theta)=1
1 solutions

Answer 461728 by lwsshak3(6761) About Me  on 2013-06-18 02:49:27 (Show Source):
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find csc(theta), given that cos(theta)=(-(√2/2)) and cot(theta)=1
Given data shows angle theta is in quadrant III where cos and sin<0, and cot>0
cot(theta)=1
theta=225º
reference angle=45º
sin(theta)=sin225º=-√2/2
csc(theta)=1/sin(theta)=-2/√2=-√2


logarithm/758874: why is it necessary to check the solutions of a logarithmic equation.
1 solutions

Answer 461727 by lwsshak3(6761) About Me  on 2013-06-18 02:30:40 (Show Source):
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why is it necessary to check the solutions of a logarithmic equation.
Because arguments of logarithms>0, that is, if the solution makes any of the arguments≤0, the solution is rejected. Example: log(x-5), x>5


Quadratic-relations-and-conic-sections/758896: Determine the equation of the hyperbola whose asymptotes are x±2y=0 and which passes through (4,3)
1 solutions

Answer 461726 by lwsshak3(6761) About Me  on 2013-06-18 02:21:28 (Show Source):
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Determine the equation of the hyperbola whose asymptotes are x±2y=0 and which passes through (4,3)
***
Hyperbola has a vertical transverse axis since it passes thru (4,3)
Its standard form of equation: (y-k)^2/a^2-(x-h)^2/b^2=1, (h,k)=(x,y) coordinates of center
Asymptotes are two straight line equations that intersect at center, y=mx+b, m=slope, b=y-intercept
Equation of asymptote with positive slope:
x-2y=0
2y=x
y=x/2
m=1/2, b=0
..
Equation of asymptote with negative slope:
x+2y=0
2y=-x
y=-x/2
m=-1/2, b=0
This means center is at (0,0)
..
slopes of asymptotes with vertical transverse axis
=±a/b=±1/2
b=±2a
b^2=4a^2
..
solving for a^2 and b^2 using coordinates of given point(4,3)
(y-k)^2/a^2-(x-h)^2/b^2=1
y^2/a^2-x^2/4a^2=1
9/a^2-16/4a^2=1
9/a^2-4/a^2=1
5/a^2=1
a^2=5
b^2=4a^2=20
Equation: y%5E2%2F5-x%5E2%2F20=1


Rate-of-work-word-problems/758903: q.1 A family of 4 members have provisions for 30 days.6 more people come to stay with them for that particular month.How long this provisions will last for them?
q.2 10men can finish constructing work in 30 days.In how many days will the house be contructed if 15 men are employed?
q.3 In a factory 20 workers make 420 toys in a day.On one particular day,five workers were were on leave.How many toys will be made on that day?

1 solutions

Answer 461725 by josgarithmetic(1774) About Me  on 2013-06-18 01:41:12 (Show Source):
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4 people have p number of provisions requiring 30 days to consume.
1 person could use p provisions over a period of 4*30 days to consume.

The analysis is to understand the pattern affecting the use of p number of provisions. Changing from 4 people to 1 person requires multiplying time by 4. Now to change from 4 people to 6 people should require multiplying by 4%2F6=2%2F3.

The short analyzed pattern should indicate 6 people need %282%2F3%29%2A30=20 days to consume the provisions.


logarithm/758907: The formula A=36.1e%5E%280.0126t%29 models the population of California. A, in million, t years after 2005.
A. What was the population in California in 2005?
B. When will the population of California reach 40 million?
If you could explain I would appreciate it, thanks in advance!
1 solutions

Answer 461724 by josgarithmetic(1774) About Me  on 2013-06-18 01:25:44 (Show Source):
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QUESTION: A. What was the population in California in 2005?

You just substitute the values and compute A.


QUESTION: B. When will the population of California reach 40 million?

Solve for t before doing anything else.
ln%28A%29=ln%2836.1e%5E%280.0126t%29%29
ln%28A%29=ln%2836.1%29%2Bln%28e%5E%280.0126t%29%29
ln%28A%29=ln%2836.1%29%2B0.0126t%2Aln%28e%29
ln%28A%29-ln%2836.1%29=0.0126t%2A1
highlight%28t=%28ln%28A%29-ln%2836.1%29%29%2F0.0126%29
Substitute the desired value for A and compute t.


test/758901: Fff
1 solutions

Answer 461723 by lenny460(837) About Me  on 2013-06-18 00:59:16 (Show Source):
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Your question is incomplete. Please repost.


Quadratic_Equations/758870: Factor: 6m%5E2%2B5m-6
1 solutions

Answer 461722 by lenny460(837) About Me  on 2013-06-18 00:57:02 (Show Source):
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Factor: 6m%5E2%2B5m-6

Answer:
(2m + 3)(3m - 2)

Check:
2m * 3m = 6m^2
2m * -2 = -4m
3 * 3m = 9m
3 * -2 = -6
6m^2 - 4m + 9m - 6
Combine like terms:
-4m + 9m = 5m
6m^2 + 5m - 6

Answer:
(2m + 3)(3m - 2)










Lennox Obuong
Algebra Tutor
Nairobi, Kenya
Email: lennoxobuong@yahoo.com


Linear-systems/758899: 6x - 5y = 3
4x + 3y = 21
Using the Substitution Method, please help me figure out how to show my work when solving.
1 solutions

Answer 461721 by fcabanski(889) About Me  on 2013-06-18 00:14:22 (Show Source):
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Substitution method:


1. Solve one equation for one of the variables.


2. Substitute that value for the variable in the second equation.


3. Solve the second equation for the remaining variable.


4. Substitute that value into the first equation to find the value of the first variable.


1. 6x - 5y = 3


6x = 5y + 3


x = (5/6)y + 1/2


2. 4x + 3y = 21 (sub (5/6)y + 1/2 for x)


4((5/6)y + 1/2) + 3y = 21


(20/6)y + 2 + 3y = 21


(10/3) y + (9/3)y = 19


19y = 57


y = 3


x = (5/6)y + 1/2


x = (5/6)* 3 + 1/2 = 5/2 + 1/2 = 6/2 = 3



Exponential-and-logarithmic-functions/758886: 7-7i divided by 2i
1 solutions

Answer 461720 by josgarithmetic(1774) About Me  on 2013-06-17 22:58:21 (Show Source):
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One might imagine i is the imaginary unit, that i*i=-1.

%287-7i%29%2F%282i%29



Percentage-and-ratio-word-problems/758881: A man has a paint formula calling for a mixture of paint A B C and D to make paint. The ratio is 60% A 25%B 10%C and 5% D. If he needs 20 gallons of paint. How many gallons of paint A will he need?
1 solutions

Answer 461719 by josgarithmetic(1774) About Me  on 2013-06-17 22:52:13 (Show Source):
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Very plainly, 60% of 20 gallons. Finding the answer requires nothing more than just that. 60% is the same as 6/10 or 3/5.


Graphs/758806: Find the equation of a circle passing through (1,2) and (3,4) and tangent to the line 3x+y=3.
1 solutions

Answer 461718 by MathLover1(6812) About Me  on 2013-06-17 22:35:07 (Show Source):
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given:
the point A(1,2)
the point B(3,4)
y=-3x%2B3
Plot A(1,2) and B(3,4)in a rectangular coordinate system.
Draw the tangent line, y=-3x%2B3, which cuts the x-axis at (1,0) .
By looking at the position of the points A, B, and at the path of the tangent
line, think that the point where the tangent touches the circle could be (1,0)
or close to.
Plan: The center of the circle is at the intersection point of the perpendicular line to tangent at the point of tangency, and the perpendicular bisector of the segment AB (reason: a tangent to a circle is perpendicular to its radius; the perpendicular bisector of a chord passes through the center).
Solution:
Let's suppose that (1,0) is the point of tangency.
Find the midpoint M of AB:
M = (%281%2B3%29%2F2, %282%2B4%29%2F2) = (2,+3)
Find the slope of the line that passes though A and B:
m+=+%284-2%29%2F3-1%29+=+1
Find the equation of the perpendicular bisector of AB (whose slope must be m%5B1%5D=-1 and passes through (2,+3)):
y+=+-1x+%2B+b; ....let (x,+y)= (2,+3)
3+=+-1%2A2+%2B+b
b+=+5
so, the equation of the perpendicular bisector of AB is
y+=+-x+%2B+5
Find the equation of the perpendicular line to the tangent (whose slope is 1%2F3 since the perpendicular lines have negative reciprocal slopes) and passes through (1,0)):
y+=+%281%2F3%29x+%2B+b;...... let (x,y)= (1,0)
0+=+%281%2F3%29%2A1+%2B+b
b+=+-1%2F3
y+=+%281%2F3%29x+-+1%2F3
Find the intersection point of y+=+-x+%2B+5 and y+=+%281%2F3%29x+-+1%2F3
-x+%2B+5+=+%281%2F3%29x+-+1%2F3
%284%2F3%29x+=+16%2F3
x+=+16%2F3+%2A+3%2F4
x+=+4 implies y+=1
So the point (4,+1)... ..=> could be the center of the circle.
If we compute the distances between (4,+1) and (1, 0), (1, 2), (3,4), we see that they have the same length, sqrt%2810%29, then we say the center of the circle is (4,1) and the radius has a length of sqrt%2810%29.
Thus, the equation of the circle that passes through (1, 2) and (3, 4) is the equation of a circle with center (4, 1) and a radius of sqrt%2810%29.
%28x+-+4%29%5E2+%2B+%28y+-+1%29%5E2+=+10
Let's solve the problem without risking extra work (we clearly see that our guess for the point of tangency was right).
After we draw the given information on the rectangular system, we would like to draw a parallel line to the tangent line that passes through the point B (3, 4).
For this we need the equation of the line to use its slope to draw it and to find the point of intersection with the perpendicular bisector of segment AB (since the center of the circle lies there; see above); (the slope is -3, since parallel line have the same slope).
y+=+-3x+%2B+b; .......let (x, y) = (3, 4)
4+=+-3%2A3+%2B+b
b+=+13
y+=+-3x+%2B+13
Let's find the intersection point of y+=+-x+%2B+5 and y+=+-3x+%2B+13
-x+%2B+5+=+-3x+%2B+13
2x+=+8
x+=+4 implies y+=+1, say the center O is at (4, 1)
Let's find the length of the congruent (O lies on the perpendicular bisector) segments OA and OB, maybe they are radii.
OA+=+OB+=+sqrt%28%284-1%292%2B%281-2%292%29+=+sqrt%2810%29.
Since the point O lies in the same time on the perpendicular bisector of AB and on the parallel line to the tangent, let's find the equation of the perpendicular line to the tangent that passes through O (the slope is 1%2F3 since the perpendicular lines have negative reciprocal slopes):
y+=+%281%2F3%29x+%2B+b;.... let (x, y) = (4, 1)
1+=+%281%2F3%29%2A4+%2B+b
b+=+-1%2F3
y+=+%281%2F3%29x+-+1%2F3
Let's find the intersection point of y+=+-3x+%2B+3 and y+=+%281%2F3%29x+-+1%2F3 (maybe this would be the point of tangency):
-3x+%2B+3+=+%281%2F3%29x+-+1%2F3
%284%2F3%29x+=+4%2F3
x+=+1 implies y+=+0; say T(1, 0)
Let's find the length of OT:
OT+=+sqrt%28%284-1%292%2B%281-0%292%29+=+sqrt%2810%29.
Since OA, OB, and OT have the same length, they are radii of the circle with center O(4, 1). So our guess was right!



Geometry_Word_Problems/758877: a rectangle has an area of 27 square inches.The length is one third as long as the width. Find the length and width of the recrtangle.
1 solutions

Answer 461717 by Alan3354(31521) About Me  on 2013-06-17 22:24:28 (Show Source):
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a rectangle has an area of 27 square inches.The length is one third as long as the width. Find the length and width of the recrtangle
-----------
3 by 9


Trigonometry-basics/758856: Determine the value of 0 to the nearest degree.
a) cot0= 3.2404
c) sec0= 1.4526
1 solutions

Answer 461716 by Alan3354(31521) About Me  on 2013-06-17 22:13:05 (Show Source):
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Determine the value of 0 to the nearest degree.
a) cot0= 3.2404
cot = 1/tan
------------
c) sec0= 1.4526
sec = 1/cos
---------------
Just use a calculator.


Triangles/758818: A right triangle having a 32.5 degree angle is inscribed in a circle with radius 42.5 cm. How long are the legs of the triangle? (Hint: A right triangle inscribed in a circle subtends a semicircle arc.)
1 solutions

Answer 461715 by Alan3354(31521) About Me  on 2013-06-17 22:11:17 (Show Source):
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A right triangle having a 32.5 degree angle is inscribed in a circle with radius 42.5 cm. How long are the legs of the triangle?
------------
Hint: The hypotenuse is the diameter = 85 cm


Trigonometry-basics/758864: -6i + i = 5i
1 solutions

Answer 461714 by Alan3354(31521) About Me  on 2013-06-17 22:09:57 (Show Source):
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-6i + i = 5i
------------
If i is used as a variable, then
-6i + i = 5i
-5i = 5i
-10i = 0
i = 0


Pythagorean-theorem/758868: a=76
c=155
what is b?
1 solutions

Answer 461713 by Alan3354(31521) About Me  on 2013-06-17 22:01:00 (Show Source):
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a=76
c=155
what is b?
-----------
No way to know.
Is b related to a & c somehow?


Money_Word_Problems/758759: A manufacturing company makes two types of water skis, a trick ski and a slalom ski. The trick ski requires 6 labor hours for fabricating and 1 labor hour for finishing. The slalom ski requires 4 labor hours for fabricating and 1 labor hour for finishing. The maximum labor hours available per day for fabricating and finishing are 108 and 24, respectively. If X is the number of trick skis and Y is the number of slalom skis produced per day, write a system of linear inequalities that indicates appropriate restraints on X and Y. Find the set of feasible solutions graphically for the number of each type of ski that can be produced.
Please help me with this, I am totally lost. Please expalin the steps so I'll understand how to solve these problems.
1 solutions

Answer 461712 by ankor@dixie-net.com(15746) About Me  on 2013-06-17 21:47:48 (Show Source):
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company makes two types of water skis, a trick ski and a slalom ski.
The trick ski requires 6 labor hours for fabricating and 1 labor
hour for finishing.
The slalom ski requires 4 labor hours for fabricating and 1 labor
hour for finishing.
The maximum labor hours available per day for fabricating and
finishing are 108 and 24, respectively.
If X is the number of trick skis and Y is the number of slalom skis
produced per day, write a system of linear inequalities that
indicates appropriate restraints on X and Y.
Find the set of feasible solutions graphically for the number of each type of ski that can be produced.
:
Fabricating equation
6x + 4y <= 108
:
Finishing equation
1x + 1y <= 24
:
since you can make negatives skis
x => 0
y => 0
:
Find the set of feasible solutions graphically for the number of each
type of ski that can be produced.
We have to put the equations into the slope/intercept to graph
6x + 4y = 108
4y = -6x + 108
divide by 4
y = -1.5x + 27; Red
and
x + y = 24
y = -x + 24; Green
Graph these two equations
+graph%28+300%2C+200%2C+-10%2C+35%2C+-10%2C+35%2C-1.5x%2B27%2C+-x%2B24%29+
The feasibility region is at or below the area bounded by the points
x=0, y=24; x=6, y=18; x=18; y=0
:
you can prove this to yourself using the fabricating equation
6x + 4y <= 108
x=6 trick skies, y=18 salom skies
6(6) + 4(18) =
36 + 72 = 108 total hrs


Polynomials-and-rational-expressions/758867: Factor x³ + 7x² - x - 7 completely
1 solutions

Answer 461711 by Edwin McCravy(8999) About Me  on 2013-06-17 21:40:18 (Show Source):
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x³ + 7x² - x - 7

Factor x² out of the first two terms and -1 out of the last two terms:

x²(x + 7) - 1(x + 7)

Factor (x + 7) of of the two terms:

(x + 7)(x² - 1)

Factor the second parentheses as the difference of two squares:

(x + 7)(x - 1)(x + 1)

Edwin