New!
Get regular updates about newly solved problems
via algebra.com's RSS system.
Recent problems solved by 'richwmiller'
richwmiller answered: 9132 problems
Jump to solutions: 0..29 , 30..59 , 60..89 , 90..119 , 120..149 , 150..179 , 180..209 , 210..239 , 240..269 , 270..299 , 300..329 , 330..359 , 360..389 , 390..419 , 420..449 , 450..479 , 480..509 , 510..539 , 540..569 , 570..599 , 600..629 , 630..659 , 660..689 , 690..719 , 720..749 , 750..779 , 780..809 , 810..839 , 840..869 , 870..899 , 900..929 , 930..959 , 960..989 , 990..1019 , 1020..1049 , 1050..1079 , 1080..1109 , 1110..1139 , 1140..1169 , 1170..1199 , 1200..1229 , 1230..1259 , 1260..1289 , 1290..1319 , 1320..1349 , 1350..1379 , 1380..1409 , 1410..1439 , 1440..1469 , 1470..1499 , 1500..1529 , 1530..1559 , 1560..1589 , 1590..1619 , 1620..1649 , 1650..1679 , 1680..1709 , 1710..1739 , 1740..1769 , 1770..1799 , 1800..1829 , 1830..1859 , 1860..1889 , 1890..1919 , 1920..1949 , 1950..1979 , 1980..2009 , 2010..2039 , 2040..2069 , 2070..2099 , 2100..2129 , 2130..2159 , 2160..2189 , 2190..2219 , 2220..2249 , 2250..2279 , 2280..2309 , 2310..2339 , 2340..2369 , 2370..2399 , 2400..2429 , 2430..2459 , 2460..2489 , 2490..2519 , 2520..2549 , 2550..2579 , 2580..2609 , 2610..2639 , 2640..2669 , 2670..2699 , 2700..2729 , 2730..2759 , 2760..2789 , 2790..2819 , 2820..2849 , 2850..2879 , 2880..2909 , 2910..2939 , 2940..2969 , 2970..2999 , 3000..3029 , 3030..3059 , 3060..3089 , 3090..3119 , 3120..3149 , 3150..3179 , 3180..3209 , 3210..3239 , 3240..3269 , 3270..3299 , 3300..3329 , 3330..3359 , 3360..3389 , 3390..3419 , 3420..3449 , 3450..3479 , 3480..3509 , 3510..3539 , 3540..3569 , 3570..3599 , 3600..3629 , 3630..3659 , 3660..3689 , 3690..3719 , 3720..3749 , 3750..3779 , 3780..3809 , 3810..3839 , 3840..3869 , 3870..3899 , 3900..3929 , 3930..3959 , 3960..3989 , 3990..4019 , 4020..4049 , 4050..4079 , 4080..4109 , 4110..4139 , 4140..4169 , 4170..4199 , 4200..4229 , 4230..4259 , 4260..4289 , 4290..4319 , 4320..4349 , 4350..4379 , 4380..4409 , 4410..4439 , 4440..4469 , 4470..4499 , 4500..4529 , 4530..4559 , 4560..4589 , 4590..4619 , 4620..4649 , 4650..4679 , 4680..4709 , 4710..4739 , 4740..4769 , 4770..4799 , 4800..4829 , 4830..4859 , 4860..4889 , 4890..4919 , 4920..4949 , 4950..4979 , 4980..5009 , 5010..5039 , 5040..5069 , 5070..5099 , 5100..5129 , 5130..5159 , 5160..5189 , 5190..5219 , 5220..5249 , 5250..5279 , 5280..5309 , 5310..5339 , 5340..5369 , 5370..5399 , 5400..5429 , 5430..5459 , 5460..5489 , 5490..5519 , 5520..5549 , 5550..5579 , 5580..5609 , 5610..5639 , 5640..5669 , 5670..5699 , 5700..5729 , 5730..5759 , 5760..5789 , 5790..5819 , 5820..5849 , 5850..5879 , 5880..5909 , 5910..5939 , 5940..5969 , 5970..5999 , 6000..6029 , 6030..6059 , 6060..6089 , 6090..6119 , 6120..6149 , 6150..6179 , 6180..6209 , 6210..6239 , 6240..6269 , 6270..6299 , 6300..6329 , 6330..6359 , 6360..6389 , 6390..6419 , 6420..6449 , 6450..6479 , 6480..6509 , 6510..6539 , 6540..6569 , 6570..6599 , 6600..6629 , 6630..6659 , 6660..6689 , 6690..6719 , 6720..6749 , 6750..6779 , 6780..6809 , 6810..6839 , 6840..6869 , 6870..6899 , 6900..6929 , 6930..6959 , 6960..6989 , 6990..7019 , 7020..7049 , 7050..7079 , 7080..7109 , 7110..7139 , 7140..7169 , 7170..7199 , 7200..7229 , 7230..7259 , 7260..7289 , 7290..7319 , 7320..7349 , 7350..7379 , 7380..7409 , 7410..7439 , 7440..7469 , 7470..7499 , 7500..7529 , 7530..7559 , 7560..7589 , 7590..7619 , 7620..7649 , 7650..7679 , 7680..7709 , 7710..7739 , 7740..7769 , 7770..7799 , 7800..7829 , 7830..7859 , 7860..7889 , 7890..7919 , 7920..7949 , 7950..7979 , 7980..8009 , 8010..8039 , 8040..8069 , 8070..8099 , 8100..8129 , 8130..8159 , 8160..8189 , 8190..8219 , 8220..8249 , 8250..8279 , 8280..8309 , 8310..8339 , 8340..8369 , 8370..8399 , 8400..8429 , 8430..8459 , 8460..8489 , 8490..8519 , 8520..8549 , 8550..8579 , 8580..8609 , 8610..8639 , 8640..8669 , 8670..8699 , 8700..8729 , 8730..8759 , 8760..8789 , 8790..8819 , 8820..8849 , 8850..8879 , 8880..8909 , 8910..8939 , 8940..8969 , 8970..8999 , 9000..9029 , 9030..9059 , 9060..9089 , 9090..9119 , 9120..9149, >>NextParallelograms/252140: Classify the quadrilateral according to the given information. List all terms that apply to each quadrilateral. In PQRS, segment PQ || segment RS and segment PQ is congruent to segment RS
the answer that i got was square, parallelogram, rectangle, and rhombus. Is that about right or does one of those not fit?
help please 1 solutions
Answer 183912 by richwmiller(9143) on 2009-12-23 12:28:20 (Show Source):
You can put this solution on YOUR website!parallelogram is all I see since we know nothing about angles
and a rhombus has four equal sides but we only know about two sides.
|
Pythagorean-theorem/252135: Design a park with the area of at least 60 square units
It must be a figure with at least 4 sides
At least one of the sides must be tilted
Find the area of the park
Find the perimeter of the park 1 solutions
Answer 183910 by richwmiller(9143) on 2009-12-23 12:15:03 (Show Source):
You can put this solution on YOUR website!An isosceles trapezoid with sides 15,23,4sqrt(2), 4sqrt(2) units
height =4 units
base angles 45 degrees
area (15+23)*4/2=72 square units
upper base is 15 units
lower base is 4+15+4=23 units
perimeter 15+23+8sqrt(2)=38+8sqrt(2)=49.31 units
|
Travel_Word_Problems/252133: Fernando’s motorboat can travel 30 mi/hr in still water.
If the boat can travel 9 miles downstream in the same time it takes to travel 1 miles upstream, what is the rate of the river’s current? 1 solutions
Answer 183903 by richwmiller(9143) on 2009-12-23 11:11:58 (Show Source):
You can put this solution on YOUR website!(30+x)*t=9
(30-x)*t=1
t=1/54 time
x=24 rate of current
another way of solving
t=9/(30+x)
t=1/(30-x)
9/(30+x)=1/(30-x)
x=24= rate of current
check
9/(30+24)=1/(30-24)
9/54=1/6
1/6=1/6
ok
|
Percentage-and-ratio-word-problems/252116: Yesterday, 20% of the animals on a farm were rabbits. Today Farmer Joe brought home five more rabbits, increasing the percentage of rabbits to 25%. How many animals were on the farm yesterday?
A. 60 B. 75 C. 80 D. 90 E. 95 1 solutions
Answer 183891 by richwmiller(9143) on 2009-12-23 07:54:09 (Show Source):
|
Travel_Word_Problems/252117: You take a trip traveling first by taxi, then by plane, then by bicycle, and finally by walking the remaining distance to your destination. The 75-mile taxi ride from your home to the airport takes 90 minutes. The 7500-mile plane trip takes 15 hours. The 500-mile bicycle trip takes 48 hours. The 5-mile walk takes 150 minutes. Your average speed for the entire trip is approximately:
A. 11.2 mph B. 50.0 mph C. 120.6 mph D. 125.2 mph E. 500.0 mph
1 solutions
Answer 183886 by richwmiller(9143) on 2009-12-23 07:38:01 (Show Source):
You can put this solution on YOUR website!add up all the small trips by distance and time
75+7500+500+5=distance=d= 8080 miles
1.5+15+48+150/60=time=t= 67 hours
d=r*t
rate(speed) =d/t=120 40/67=120.6 mph
c. 120.6 mph
|
Miscellaneous_Word_Problems/252118: toothpaste tube holds 250 cm^3 of toothpaste. The nozzle of the tube is round with a diameter of 5 mm. Assume that the toothpaste is deposited on the counter in a straight line such that the diameter is the same as that of the nozzle (0.5 cm). Approximately how long a line of toothpaste can be made with a full tube of toothpaste?
A. 79.6 cm B. 250 cm C. 4000 cm D. 3.18 m E. 12.73 m
1 solutions
Answer 183884 by richwmiller(9143) on 2009-12-23 07:31:37 (Show Source):
|
Miscellaneous_Word_Problems/252119: In Mr. Hoolihan’s class, every student voted once for class president. Vonda received 10% of the votes, Emma received 35% of the votes, Frank received 30% of the votes, and Bobby received the remaining 10 votes. What was the difference between the least number of votes received by a candidate and the greatest number of votes received by a candidate?
A. 4 B. 6 C. 10 D. 12 E. 14
1 solutions
Answer 183882 by richwmiller(9143) on 2009-12-23 07:24:17 (Show Source):
You can put this solution on YOUR website!Let 1.00*x=total votes
.10x+.35x+.30x+10=1.00x
x=40 votes
vonda.10x=4
emma .35(40)=14
frank .30*40=12
bobby 10
difference 14-4=10
|
Miscellaneous_Word_Problems/252087: A decorator plans to place a rug in a room with the dimensions of 9 meters by 12 meters in such a way that a uniform strip of flooring around the rug will remain uncovered. If the rug is to cover 1/2 the floor space, what should the dimensions of the rug be?
equation and answer please. 1 solutions
Answer 183847 by richwmiller(9143) on 2009-12-22 20:35:37 (Show Source):
You can put this solution on YOUR website!9*12=108 sq meters
so only 54 sq meters are to be covered
9*6 is neat and clean but the decorator wants the rug to be centralized in the room with even space around it. This would leave exactly one half of the room bare
(9-x)(12-x)=54
108-21x+x^2=54
54-21x+x^2
x=3 and x=18
x=18 gives us negative dimensions
6*9 actually gives us 1.5 meters all around.
but the rug will be turned so that the length of 9 meters will go on the 12 meter length of the room.
|
Graphs/252086: how do you solve this equation and graph it.
3x+8y-6=0 1 solutions
Answer 183845 by richwmiller(9143) on 2009-12-22 20:24:43 (Show Source):
You can put this solution on YOUR website!It can't be "solved" because you haven't asked any questions about it.
If there were another equation I could tell you where they meet or that they don't meet
There are many solutions because there are two unknowns.
I can tell you the slope. I can tell you where x=0 and y=0.
I can get another equation parallel or even perpendicular to it.
If you give me a point (ordered pair) I can tell you if it is on this line.
I can make another equation that will have the same solution set.
Graph it by picking any x of your choosing and calculate y.
Usually for a linear equation we pick where x is zero and y is zero
|
Numbers_Word_Problems/252089: Can I please get help on this word problem? The sum of two numbers is 46. Four times one number is 4 more than twice the other number. Find the numbers. So far I have tried many times but always end up with an impossible answer. One thing I have tried is, 4x + 2x + 4 = 6(42). But I always end up getting 41 and 1/3. Can you please teach me how to do this problem? 1 solutions
Answer 183842 by richwmiller(9143) on 2009-12-22 20:18:31 (Show Source):
You can put this solution on YOUR website!First we have two unknowns and need two equations.
The first thing we learn is the two numbers add up to 46
n+m=46
Now the next part is a bit hard to understand so lets break it down.
(four times one number)4n
It doesn't matter at this point which one- n or m will do.
so I choose n
then it says that 4n is (means =} 4 more (4+ )than twice the other number 2m
4n=4+2m
so now we have our two equations in two unknowns
n+m=46
4n=4+2m
solve the first one for either m or n it doesn't matter
n=46-m
or
m=46-n
just choose one and stick with it all the way
4n=4+2m
every time we see n in the above equation we will put 46-m
4(46-m)=4+2m
now we have one equation with one unknown
so now we just have bring everything together and combine and get the all the m's on one side and all the numbers on the pother
first let's multiply out
4*46-4m=4+2m
add 4 m to both sides
4*46=4+6m
4*45+4*1=4*1+6m
subtract 4*1 from both sides
4*45=6m
(2*2)*(3*15)
2*3*2*15=6m
6*30=6m
divide by 6
30=m
46-m=n
46-30=n
16=n
so far so good
now we go back to the second equation and check our work
4n=4+2m
4*16=4+2(30)
64=64
ok
|
Rectangles/252070: the width of a rectangle is 3 yards less than its legth. the perimeter is 130 yards. find the length and width of the rectangle show the work 1 solutions
Answer 183805 by richwmiller(9143) on 2009-12-22 16:04:09 (Show Source):
|
Expressions-with-variables/252056: Two cyclists start biking from a trails start 3 hrs apart. The second cyclist travels at 10 mph and starts 3 hours after the first cyclist who is traveling at 6 mph. How much time will pass before the second cyclist catches up with the first from the time the second cyclist started cycling. I know d=rt. I tried
d=10(t-3)/6t?
1 solutions
Answer 183798 by richwmiller(9143) on 2009-12-22 15:22:53 (Show Source):
You can put this solution on YOUR website!You are close. I appreciate that you mention what you tried.
What will be the same for both of them?
not the speed not the time but the distance.
d=rt
r1*t1=d1
r2*t2=d2
d1=d2
r1*t1=r2*t2=
t1=t+3
t2=t
6*(t+3)=10t
t=9/2
t=4.5
so instead of dividing them we make them equal.
Using t for the 10 mph means that the time t will be the answer to the question asked about the second cyclist. I also don't like dealing with negatives.
check
6*7.5=10*4.5
45=45
ok
BTW
We could have used t-3
6*(t)=10(t-3)
t=15/2=7.5
but we weren't asked about this guy
so we have to subtract 3
7.5-3=t-3
|
Linear-equations/252036: which ordered pair is a solution of the equation 5x+3y=-2
1,0
1,-1
-1,1
0,1 1 solutions
Answer 183784 by richwmiller(9143) on 2009-12-22 11:55:06 (Show Source):
You can put this solution on YOUR website!plug them into 5x+3y=-2
and when you get -2=-2 that is the solution
if you get anything but -2=-2 it is not a solution
what would gives us -2
5-3=+2
so the x must be negative and the y positive
There is one solution like that
|
Rational-functions/252033: I am trying to solve an addition rational problem by finding the LCD. Thank you for your help. 1 solutions
Answer 183782 by richwmiller(9143) on 2009-12-22 11:50:11 (Show Source):
You can put this solution on YOUR website!You have three denominators :m^2, n and m
Clearly m is a factor of m^2
so the common denominator will be nm^2
so multiply the fraction with m^2 as the denominator by n/n
the n denominator by m^2/m^2
the m denominator by mn/mn
The parts with no denominator by nm^2/nm^2
nm^4 +n^3 -m^2*n^4 +nm^3- nm^3+ m^2n^2+m^2n^2
now combine terms
nm^4-m^2n^4+n^3+2m^2n^2
All over nm^2
|
percentage/252032: Mrs.Jones paid $55.73 over regular price for some clothes because of financing them at 19% for 8 months. How much was the regular price of the clothes? 1 solutions
Answer 183781 by richwmiller(9143) on 2009-12-22 11:37:30 (Show Source):
|
Quadratic_Equations/252024: 4x^2-4x+3=0
Move the constant to the right side of the equation.
Multiply each term in the equation by four times the coefficient of the x^2 term.
Square the coefficient of the original x term and add it to both sides of the equation
Take the square root of both sides.
Set the left side of the equation equal to the positive square root of the number on the right side and solve for x
Set the left side of the equation equal to the negative square root of the number on the right side of the equation and solve for x. 1 solutions
Answer 183779 by richwmiller(9143) on 2009-12-22 11:32:44 (Show Source):
You can put this solution on YOUR website!I am assuming the steps you mention are what you have tried.
The second should be divide both sides by 4 (the coefficient of x^2)
third step should be take 1/2 the coefficient of x and square it and then add it to both sides
Possible intermediate steps:
4 x^2-4 x+3 = 0
Solve the quadratic equation by completing the square:
Divide both sides by 4:
x^2-x+3/4 = 0
Subtract 3/4 from both sides:
x^2-x = -3/4
Add 1/4 to both sides:
x^2-x+1/4 = -1/2
Factor the left hand side:
(x-1/2)^2 = -1/2
Take the square root of both sides:
|x-1/2| = i/sqrt(2)
Eliminate the absolute value:
x-1/2 = -i/sqrt(2) or x-1/2 = i/sqrt(2)
Add 1/2 to both sides:
x = 1/2 (1-i sqrt(2)) or x-1/2 = i/sqrt(2)
Add 1/2 to both sides:
x = 1/2 (1-i sqrt(2)) or x = 1/2 (1+i sqrt(2))
| Solved by pluggable solver: SOLVE quadratic equation with variable |
Quadratic equation (in our case ) has the following solutons:

For these solutions to exist, the discriminant should not be a negative number.
First, we need to compute the discriminant : .
The discriminant -32 is less than zero. That means that there are no solutions among real numbers.
If you are a student of advanced school algebra and are aware about imaginary numbers, read on.
In the field of imaginary numbers, the square root of -32 is + or - .
The solution is 
Here's your graph:
 |
| Solved by pluggable solver: SOLVE quadratic equation with variable |
Quadratic equation (in our case ) has the following solutons:

For these solutions to exist, the discriminant should not be a negative number.
First, we need to compute the discriminant : .
The discriminant -2 is less than zero. That means that there are no solutions among real numbers.
If you are a student of advanced school algebra and are aware about imaginary numbers, read on.
In the field of imaginary numbers, the square root of -2 is + or - .
The solution is 
Here's your graph:
 |
4x^2-4x+3=0
|
Equations/252027: 1. Which ordered pair is the solution of the following system of equations?
3x+2y=4
-2x+2y=24 1 solutions
Answer 183777 by richwmiller(9143) on 2009-12-22 11:15:51 (Show Source):
You can put this solution on YOUR website! 3x+2y=4
-2x+2y=24
subtract the second from the first
5x=-20
x=-4
3*(-4)+2y=4
-12+2y=4
2y=16
y=8
(-4,8)
check on second equation
-2(-4)+(2*8)=24
8+16=24
24=24 ok
check first equation
3*(-4)+2*8=4
-12+16=4
4=4 ok
|
|