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x-y=5
3x+y=3 1 solutions
Answer 151054 by nerdybill(6963) on 2009-06-22 07:23:41 (Show Source):
You can put this solution on YOUR website!Applying the substitution method:
x-y=5 (equation 1)
3x+y=3 (equation 2)
.
Solve equation 1 for x:
x-y=5
x = y+5
Substitute the above into equation 2 and solve for y:
3x+y=3
3(y+5)+y=3
3y+15+y=3
4y+15=3
4y = -12
y = -3
.
Substitute the above into equation 1 and solve for x:
x-y=5
x-(-3)=5
x+3 = 5
x = 2
.
Solution:
x=2 and y=-3
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Linear_Algebra/200775: Give an ordered pair (x,y) of numbers that satisfy the equations
6x + y = 4 1 solutions
Answer 151014 by nerdybill(6963) on 2009-06-21 15:31:13 (Show Source):
You can put this solution on YOUR website!Give an ordered pair (x,y) of numbers that satisfy the equations
6x + y = 4
.
Simply pick a value for 'x' (say 1), substitute it in and solve for y:
If x = 1
6(1) + y = 4
6 + y = 4
y = -2
.
Therefore, an ordered pair would be:
(1, -2)
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Linear-systems/200689: Find the domain of the rational function
h(x)= x-80 over x to the 3rd - 2x to the 2nd - 35x
1 solutions
Answer 151013 by nerdybill(6963) on 2009-06-21 15:29:12 (Show Source):
You can put this solution on YOUR website!Find the domain of the rational function
h(x)= x-80 over x to the 3rd - 2x to the 2nd - 35x
.
Domain is all real numbers EXCEPT when 'x' makes the denominator zero.
Find those exceptions by setting the denominator to zero and solving for x:

x = {0, 7, -5}
.
Therefore, the domain is
"All real numbers, except for 0, 7 and -5"
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Polynomials-and-rational-expressions/200768: Please help me solve:
The length of a triangle are as follows:
height is 8 feet, base across is 12 feet, what is the lenght of the triangle?
It looks like an isoceles triangle.
Answer:
a=base
b=?
h=height
h=sqrt(b^2-1/4a^2)
8=sqrt(b^2-1/4(12^2)
8=sqrt(b^2-1/4(144)
8=sqrt(b^2-36)
8=b-6
14=b
Please confirm if my answer is ccorrect?
Thanks a bunch 1 solutions
Answer 151004 by nerdybill(6963) on 2009-06-21 13:06:57 (Show Source):
You can put this solution on YOUR website!height is 8 feet, base across is 12 feet, what is the lenght of the triangle?
It looks like an isoceles triangle.
.
Find the length via the Pythagorean theorem where
length of triangle is the hypotenuse
height is one side
half the base is the other side
.
Let x = length of triangle
8^2 + 6^2 = x^2
64 + 36 = x^2
100 = x^2
sqrt(100) = x
{-10, 10} = x
Throw out negative answer:
10 feet =x
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Rectangles/200752: A rectangle is 4 meters longer than it is wide. The area of the rectangle is 252 square meters. Find the length and width of the rectangle.
length = ________ m width = ________ m 1 solutions
Answer 151000 by nerdybill(6963) on 2009-06-21 12:24:57 (Show Source):
You can put this solution on YOUR website!A rectangle is 4 meters longer than it is wide. The area of the rectangle is 252 square meters. Find the length and width of the rectangle.
.
Let w = width of rectangle
then
w+4 = length of rectangle
.
w(w+4) = 252
w^2+4w = 252
w^2+4w-252 = 0
(w-14)(w+18) = 0
w = {14, -18}
Throw out the negative solution leaving:
w = 14 meters (width)
.
w+4 =14+4 = 18 meters (length)
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Rate-of-work-word-problems/200766: pat can read at a constant rate of 400 pages per 8 hours . how many seconds does it take pat to read one page ? 1 solutions
Answer 150990 by nerdybill(6963) on 2009-06-21 12:01:08 (Show Source):
You can put this solution on YOUR website!pat can read at a constant rate of 400 pages per 8 hours . how many seconds does it take pat to read one page ?
.
400 pages/ 8 hr = 1 page per .02 hr
.
1 pg 1 hr 1 min
-------- x ------ x ------
8.02 hr 60 min 60 sec
.
= 1/72 (1 page per 72 seconds)
.
ans: 72 seconds
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Graphs/200735: This question is from textbook Beginning and Intermediate Algebra
How do you find the X and Y intercepts and then graph the line 1 solutions
Answer 150954 by nerdybill(6963) on 2009-06-20 23:04:09 (Show Source):
You can put this solution on YOUR website!How do you find the X and Y intercepts and then graph the line
.
Given your equation...
.
1. to find the x-intercept, set 'y'=0 and solve for x
Your x-intercept will then be at ("value found", 0)
.
2. to find the y-intercept, set 'x'=0 and solve for y
Your y-intercept will then be at (0, "value found")
.
3. plot the two points found above in an x-y graph and draw a line through the two points -- that's it, you're done.
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Miscellaneous_Word_Problems/200679: two angles are complementary if the sum of their measures 90 degrees. Themeasure of the first angle is 5 degrees less than 4 times the second angle. What is the measure of the first angle. 1 solutions
Answer 150925 by nerdybill(6963) on 2009-06-20 08:57:06 (Show Source):
You can put this solution on YOUR website!two angles are complementary if the sum of their measures 90 degrees. Themeasure of the first angle is 5 degrees less than 4 times the second angle. What is the measure of the first angle.
.
Let x = second angle
then
4x-5 = first angle
.
x + 4x-5 = 90
x + 4x = 95
5x = 90
x = 18 degrees (second angle)
.
First angle:
4x-5 = 4(18)-5 = 72-5 = 67 degrees (first angle)
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Mixture_Word_Problems/200681: Please I need help with this. Find x if shaded area is 90.the (whole rectangle is shaded except for the holes) By developing and solving by factoring quadratic equation. The rectangle width is 2x-2, length is 3x, and there are 3 holes cut out with the width of x and length of x-1. I know l*w=A but how do you take out the hole squares? 1 solutions
Answer 150924 by nerdybill(6963) on 2009-06-20 08:53:47 (Show Source):
You can put this solution on YOUR website!Please I need help with this. Find x if shaded area is 90.the (whole rectangle is shaded except for the holes) By developing and solving by factoring quadratic equation. The rectangle width is 2x-2, length is 3x, and there are 3 holes cut out with the width of x and length of x-1. I know l*w=A but how do you take out the hole squares?
.
Area of rectangle = (3x)(2x-2)
.
Area of one hole = x(x-1)
Three holes would then be 3x(x-1)
.
"Shaded area" = "area of rectangle" - "area of holes"
90 = (3x)(2x-2) - 3x(x-1)
On the right side, distribute:
90 = (6x^2-6x) - (3x^2-3x)
90 = 6x^2-6x - 3x^2+3x
90 = 3x^2-3x
0 = 3x^2-3x-90
0 = x^2-x-30
Factoring:
0 = (x-6)(x+5)
x = {-5, 6}
Throwing out the negative solution we get:
x = 6
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Functions/200612: h(x)= x-3/x^3-4x
What is the domain of the function 1 solutions
Answer 150860 by nerdybill(6963) on 2009-06-19 12:32:10 (Show Source):
You can put this solution on YOUR website!
.
Domain specifies the values 'x' can take.
The only thing we have to worry about is if the denominator goes to zero.
.
So, set the denominator to zero and solve for x:
x^3-4x = 0
x(x^2-4) = 0
.
So, the denominator goes to zero if:
x=0 or x^2-4=0
.
Therefore,
x = all real numbers EXCEPT: x=0, x=-2, x=2
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Miscellaneous_Word_Problems/200610: The amount of an investment of P dollars for t years at simple interest rate r is given by A = P + prt
Rewrite this formula by factoring out the greatest common factor on the right-hand side.
1 solutions
Answer 150859 by nerdybill(6963) on 2009-06-19 12:28:21 (Show Source):
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Rational-functions/200602: dap5654@aol.com. I am in intermediate algebra. I am having trouble with equations with rational expressions.
Could you help me solve this equation? ? I think the answer is 3,4. 1 solutions
Answer 150851 by nerdybill(6963) on 2009-06-19 11:40:29 (Show Source):
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Travel_Word_Problems/200494: This question is from textbook Elementary and Intermediate Algebra
Avoiding a collision. A car is traveling on a road that
is perpendicular to a railroad track. When the car is
30 meters from the crossing, the car’s new collision
detector warns the driver that there is a train 50 meters
from the car and heading toward the same crossing. How
far is the train from the crossing? 1 solutions
Answer 150734 by nerdybill(6963) on 2009-06-18 08:04:48 (Show Source):
You can put this solution on YOUR website!Avoiding a collision. A car is traveling on a road that
is perpendicular to a railroad track. When the car is
30 meters from the crossing, the car’s new collision
detector warns the driver that there is a train 50 meters
from the car and heading toward the same crossing. How
far is the train from the crossing?
.
Applying Pythagorean theorem:
Let x = train's distance from crossing
then
x^2 + 30^2 = 50^2
x^2 = 50^2 - 30^2
x^2 = 2500 - 900
x^2 = 1600
x = 
x = 40 meters
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Miscellaneous_Word_Problems/200371: Amount of an investment. The amount of an investment
of P dollars for t years at simple interest rate r is given by
A = P + Prt.
a) Rewrite this formula by factoring out the greatest
common factor on the right-hand side.
b) Find A if $8300 is invested for 3 years at a simple
interest rate of 15%. 1 solutions
Answer 150670 by nerdybill(6963) on 2009-06-17 11:15:41 (Show Source):
You can put this solution on YOUR website!Amount of an investment. The amount of an investment
of P dollars for t years at simple interest rate r is given by
A = P + Prt.
a) Rewrite this formula by factoring out the greatest
common factor on the right-hand side.
A = P + Prt
Factoring out a P:
A = P(1 + rt)
.
b) Find A if $8300 is invested for 3 years at a simple
interest rate of 15%.
A = P(1 + rt)
A = 8300(1 + .15(3))
A = 8300(1 + .45)
A = 8300(1.45)
A = $12035
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Expressions-with-variables/200374: Hello,
I need some help. I keep trying the following problem and am not sure what I am doing wrong. I am not sure if I am changing the signs in the right places. The problem and what I have so far are as follows:
Perform the indicated operations:
(x^2 - 4x + 1) - (-8x^2 + 2x - 6) - (x^2 + 3x + 3/5)
x^2 - 8x^2 - x^2 - 4x + 2x + 3x + 1 - 6 + 3/5
Can you please help. Thank you in advance.
1 solutions
Answer 150662 by nerdybill(6963) on 2009-06-17 06:47:29 (Show Source):
You can put this solution on YOUR website!(x^2 - 4x + 1) - (-8x^2 + 2x - 6) - (x^2 + 3x + 3/5)
x^2 - 8x^2 - x^2 - 4x + 2x + 3x + 1 - 6 + 3/5 (Error!!)
.
You MUST distribute the negative sign to ALL terms within the ():
(x^2 - 4x + 1) - (-8x^2 + 2x - 6) - (x^2 + 3x + 3/5)
Distributing negative to terms in second ():
(x^2 - 4x + 1) + 8x^2 - 2x + 6 - (x^2 + 3x + 3/5)
Distributing negative to terms in last ():
(x^2 - 4x + 1) + 8x^2 - 2x + 6 - x^2 - 3x - 3/5
x^2 - 4x + 1 + 8x^2 - 2x + 6 - x^2 - 3x - 3/5
Grouping terms:
x^2 + 8x^2 - x^2 - 4x - 2x - 3x + 1 + 6 - 3/5
8x^2 - 9x + 1 + 6 - 3/5
8x^2 - 9x + 5/5 + 30/5 - 3/5
8x^2 - 9x + 35/5 - 3/5
8x^2 - 9x + 32/5
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Miscellaneous_Word_Problems/200373: Area of a painting. A rectangular painting with a width of
x centimeters has an area of x^2 +50x square centimeters.
Find a binomial that represents the length. See the accompanying
figure. 1 solutions
Answer 150661 by nerdybill(6963) on 2009-06-17 06:38:34 (Show Source):
You can put this solution on YOUR website!Area of a painting. A rectangular painting with a width of
x centimeters has an area of x^2 +50x square centimeters.
Find a binomial that represents the length. See the accompanying
figure.
.
Since,
length*width = area
.
Given:
width = x
area = x^2 + 50x
.
Plug in what was given:
length(x) = x^2 + 50x
dividing both sides by x:
length = x + 50 (this is what they're looking for)
|
Pythagorean-theorem/200344: A wagon wheel is placed against a wall. One point on the edge of the wheel is 5 inches from the ground and 10 inches from the wall. What is the radius of the wheel?
1 solutions
Answer 150655 by nerdybill(6963) on 2009-06-17 00:05:11 (Show Source):
You can put this solution on YOUR website!A wagon wheel is placed against a wall. One point on the edge of the wheel is 5 inches from the ground and 10 inches from the wall. What is the radius of the wheel?
.
Think Pythagorean theorem.
.
Draw a diagram -- the wheel is the hypotenuse while the wall and the floor forms the two sides of a right triangle.
.
Let d = diameter of wheel
then
d^2 = 5^2 + 10^2
d^2 = 25 + 100
d^2 = 125
d = 
d = 
d = 
.
Radius is half the diameter:
radius =  = 5.59 inches
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Linear_Equations_And_Systems_Word_Problems/200360: A jazz concert brought in $191,000 on the sale of 7400 tickets, if tickets were sold for $20 and $30 each, how many of each type of ticket were sold? 1 solutions
Answer 150654 by nerdybill(6963) on 2009-06-16 23:58:01 (Show Source):
You can put this solution on YOUR website!A jazz concert brought in $191,000 on the sale of 7400 tickets, if tickets were sold for $20 and $30 each, how many of each type of ticket were sold?
.
Let x = number of $20 tickets sold
then
7400-x = number of $30 tickets sold
.
20x + 30(7400-x) = 191000
20x + 222000 - 30x = 191000
20x - 30x = -31000
-10x = -31000
x = 3100 ($20 tickets)
.
$30 tickets:
7400-x = 7400-3100 = 4300 ($30 tickets)
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Graphs/200358: HI everyone, Im trying to finish the following problems but I am struggling a bit. I have to show full working and comment on the outcomes. I dont expect answers to all 3, but if someone can show me one of each type that would be super.
Question 1. Find the equation of the line that passes through the point (-2,5) and parallel to the y axis.
Question 2. Find the equation of the line passing through (1,3) and parallel to the line y = 3/2 x - 1/2.
Question 3. A line with the gradient passes through the point (1,3). Find the equation of the line.
Thanks for your help. -Nick. 1 solutions
Answer 150653 by nerdybill(6963) on 2009-06-16 23:54:10 (Show Source):
You can put this solution on YOUR website!Question 1. Find the equation of the line that passes through the point (-2,5) and parallel to the y axis.
x = -2
.
Question 2. Find the equation of the line passing through (1,3) and parallel to the line y = 3/2 x - 1/2.
If a two lines are parallel, the slopes are the same.
Our line has a slope of 3/2 crossing (1,3)
plug into point-slope form
y-y1 = m(x-x1)
y-3 = (3/2)(x-1)
y-3 = (3/2)x - 3/2
y = (3/2)x - 3/2 + 3
y = (3/2)x - 3/2 + 6/2
y = (3/2)x + 3/2
.
Question 3. A line with the gradient 2 passes through the point (1,3). Find the equation of the line.
Gradient is equivalent to the slope
So m = 2 and it crosses (1,3)
plug into point-slope form
y-y1 = m(x-x1)
y-3 = 2(x-1)
y-3 = 2x-2
y = 2x + 1
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Linear-equations/200311: A student has earned scores of 87, 81, and 88 on the first 3 of 4 tests. If the student wants an average (arithmetic mean) of exactly 87, what score must she earn on the fourth test? 1 solutions
Answer 150584 by nerdybill(6963) on 2009-06-16 14:44:20 (Show Source):
You can put this solution on YOUR website!A student has earned scores of 87, 81, and 88 on the first 3 of 4 tests. If the student wants an average (arithmetic mean) of exactly 87, what score must she earn on the fourth test?
.
Let x = score on fourth test
then
(x+87+81+88)/4 = 87
(x+256)/4 = 87
Multiplying both sides by 4:
(x+256) = 87*4
(x+256) = 348
x = 348-256
x = 92 (score for fourth test)
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Rational-functions/200114: A community water tank can be filled in 10 hours by the town office well alone and in 16 hours by the high school well alone. How long will it take to fill the tank if both wells are working together? 1 solutions
Answer 150437 by nerdybill(6963) on 2009-06-15 08:52:08 (Show Source):
You can put this solution on YOUR website!A community water tank can be filled in 10 hours by the town office well alone and in 16 hours by the high school well alone. How long will it take to fill the tank if both wells are working together?
.
Rate of town office well: 1 tank per 10 hours : 1/10
Rate of high school well: 1 tank per 16 hours : 1/16
.
Let x = number of hours required for both wells
then
x(1/10 + 1/16) = 1
x/10 + x/16) = 1
Multiplying both sides by 160 (common denominator):
16x + 10x = 160
26x = 160
x = 160/26
x = 6.154 hours
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Geometry_Word_Problems/200118: Cheyenne will drive 3,000 miles across Interstate 90. She plans to drive 7 hours each day averaging 60 miles per hour. What is the least number of days the trip will take?
1 solutions
Answer 150436 by nerdybill(6963) on 2009-06-15 08:45:28 (Show Source):
You can put this solution on YOUR website!Cheyenne will drive 3,000 miles across Interstate 90. She plans to drive 7 hours each day averaging 60 miles per hour. What is the least number of days the trip will take?
.
Applying the distance formula:
d = rt
where
d is distance traveled
r is rate or speed
t is time
.
Each day Cheyenne travels:
7*60 = 420 miles
.
Number of days, then, to travel 3000 miles:
3000/420 = 7.143
Since she takes MORE than 7 days, the "least" number of days then is
8 days (answer)
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