New!
Get regular updates about newly solved problems
via algebra.com's RSS system.
Recent problems solved by 'checkley77'
checkley77 answered: 12560 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 , 9150..9179 , 9180..9209 , 9210..9239 , 9240..9269 , 9270..9299 , 9300..9329 , 9330..9359 , 9360..9389 , 9390..9419 , 9420..9449 , 9450..9479 , 9480..9509 , 9510..9539 , 9540..9569 , 9570..9599 , 9600..9629 , 9630..9659 , 9660..9689 , 9690..9719 , 9720..9749 , 9750..9779 , 9780..9809 , 9810..9839 , 9840..9869 , 9870..9899 , 9900..9929 , 9930..9959 , 9960..9989 , 9990..10019 , 10020..10049 , 10050..10079 , 10080..10109 , 10110..10139 , 10140..10169 , 10170..10199 , 10200..10229 , 10230..10259 , 10260..10289 , 10290..10319 , 10320..10349 , 10350..10379 , 10380..10409 , 10410..10439 , 10440..10469 , 10470..10499 , 10500..10529 , 10530..10559 , 10560..10589 , 10590..10619 , 10620..10649 , 10650..10679 , 10680..10709 , 10710..10739 , 10740..10769 , 10770..10799 , 10800..10829 , 10830..10859 , 10860..10889 , 10890..10919 , 10920..10949 , 10950..10979 , 10980..11009 , 11010..11039 , 11040..11069 , 11070..11099 , 11100..11129 , 11130..11159 , 11160..11189 , 11190..11219 , 11220..11249 , 11250..11279 , 11280..11309 , 11310..11339 , 11340..11369 , 11370..11399 , 11400..11429 , 11430..11459 , 11460..11489 , 11490..11519 , 11520..11549 , 11550..11579 , 11580..11609 , 11610..11639 , 11640..11669 , 11670..11699 , 11700..11729 , 11730..11759 , 11760..11789 , 11790..11819 , 11820..11849 , 11850..11879 , 11880..11909 , 11910..11939 , 11940..11969 , 11970..11999 , 12000..12029 , 12030..12059 , 12060..12089 , 12090..12119 , 12120..12149 , 12150..12179 , 12180..12209 , 12210..12239 , 12240..12269 , 12270..12299 , 12300..12329 , 12330..12359 , 12360..12389 , 12390..12419 , 12420..12449 , 12450..12479 , 12480..12509 , 12510..12539 , 12540..12569, >>Nexttest/162785: This question is from textbook Elementary and Intermediate
104) Venture captial. Henry invested $12,000 in a new restaurant. When the restaurant was sold two years later, be received $27,000. Find his average annual return by solving the equation 12,000(1+r)^2 = 27,000 1 solutions
Answer 119993 by checkley77(12569) on 2008-10-18 17:06:44 (Show Source):
You can put this solution on YOUR website!12,000(1+r)^2 = 27,000
12,000(1+2R+R^2)=27,000
12,000+24,000R+12,000R^2=27,000
12,000R^2+24,000R+12,000-27,000=0
12,000R^2+24,000R-15,000=0
3,000(4R^2+8R-5)=0
3,000(2R-1)(2R+5)=0
2R-1=0
2R=1
R=1/2 OR .5 OR 50% ANNUAL RETURN.
PROOF:
12,000(1+.5)^2=27,000
12,000(1.5)^2=27,000
12,000*2.25=27,000
27,000=27,000
|
Mixture_Word_Problems/162791: A chemist needs a saline solution that is 20% sodium chloride but only has solutions that are 15% and 40% sodium cholride. If the chemist measures 150mL of the 15% solution, how many milliliters of the 40% solution should she add to make a 20% solution? 1 solutions
Answer 119990 by checkley77(12569) on 2008-10-18 16:53:54 (Show Source):
You can put this solution on YOUR website!.40X+.15(150-X)=.20*150
.40X+22.5-.15X=30
.25X=30-22.5
.25X=7.5
X=7.5/.25
X=30 ML OF 40% SOLUTION IS USED.
150-30=120 ML OF 15% SOLUTION IS USED.
PROOF:
.40*30+.15*120=.20*150
12+18=30
30=30
|
Travel_Word_Problems/162799: A cattle train left Miami and traveled toward New York. 14 hours later a diesel train left traveling at 45 km/h in an effort to catch up to the cattle train. After traveling for four hours the diesel train finally caught up. What was the cattle train's average? (The answer is 10km/hr; what is step by step solution)? 1 solutions
Answer 119989 by checkley77(12569) on 2008-10-18 16:44:08 (Show Source):
You can put this solution on YOUR website!D=RT
D=45*4
D=180 KILOMETERS IS THE DISTANCE THE DIESEL TRAIN VELED.
180=X(14+4)
180=X*18
X=180/18
X=10 KMH WAS THE SPEED OF THE CATTLE TRAIN.
|
Polynomials-and-rational-expressions/162797: This question is from textbook
A photo is 3 inches longer than it is wide. A 2 inch border is placed around the photo making the total area of the photo and border 180 square inches. What are the dimensions of the photo? 1 solutions
Answer 119987 by checkley77(12569) on 2008-10-18 16:24:37 (Show Source):
You can put this solution on YOUR website!(x+4)(x+3+4)=180 the +4 in each term is the border measurement.
(x+4)(x+7)=180
x^2+11x+28-180=0
x^2+11x-152=0
(x-8)(x+19)=0
x-8=0
x=8 is the width of the photo.
8+3=11 is the length of the photo.
Proof:
(8+4)(11+4)=180
12*15=180
180=180
|
Miscellaneous_Word_Problems/162794: A car rental company has two rental rates. Rate 1 is $72 per day plus $0.16 per mile. Rate 2 is $144 per day plus $0.08 per mile. If you plan to rent for one week, how many miles would you need to drive to pay less by taking rate 2? 1 solutions
Answer 119985 by checkley77(12569) on 2008-10-18 16:18:37 (Show Source):
|
Geometry_Word_Problems/162795: Brothers Matt and Jeph are leaning a 20-foot ladder against their house. If the ladder reaches 15 feet up the house, how far is the bottom of the ladder from the base of the house? Round to the nearest tenth.
I tried doing
A squared + B squared = C squared and I got 400+225=625 and my answer came out to be 25ft after I found the square root of 625. I just want to know if i'm right. 1 solutions
Answer 119983 by checkley77(12569) on 2008-10-18 16:08:43 (Show Source):
|
Graphs/162725: Please help.
Solve by the elimination method.
3x + 4y=3
6x + 8y=6
What is the solution of the system?
(Type an ordered pair. Type an integer or a fraction. Type N if there is no solution. Type I if there are infinitely more solutions.)
1 solutions
Answer 119955 by checkley77(12569) on 2008-10-18 09:08:46 (Show Source):
|
Graphs/162741: are these line parallel perpendicular or neither?
5x+3y=3
3x-5y=9 1 solutions
Answer 119953 by checkley77(12569) on 2008-10-18 08:59:18 (Show Source):
You can put this solution on YOUR website!5x+3y=3
3y=-5x+3 this line has a slope=-5 (red line)
3x-5y=9
-5y=-3x+9
y=-3x/-5+9/-5
y=3x/5-9/5 this line has a slope=-3/5 (green line)
 (graph 300x300 pixels, x from -10 to 10, y from -10 to 10, of TWO functions -5x +3 and 3x/5 -9/5).
These line are neither.
|
Polynomials-and-rational-expressions/162743: a.
A rectangular parking lot is 100 ft longer than it is wide. Determine the dimensions of the parking lot if it measures 500 ft diagonally.
b.
Three consecutive odd integers are such that the square of the third is 264 more than the square of the second. Find the three integers. 1 solutions
Answer 119952 by checkley77(12569) on 2008-10-18 08:52:31 (Show Source):
You can put this solution on YOUR website!(x+100)^2+x^2=500^2
x^2+200x+10,000+x^2=250,000
2x^2+200x+10,000-250,000=0
2x^2+200x-240,000=0
2(x^2+100x-120,000)=0
2(x-300)(x+400)=0
x-300=0
x=300 is the width.
300+100=400 is the length.
Proof:
400^2+300^2=250,000
160,000+90,000=250,000
250,000=250,000
------------------------------------------
let x, x+2 & x+4 be the 3 integers.
(x+4)^2=(x+2)^2+264
x^2+8x+16=x^2+4x+4+264
8x-4x=264-16+4
4x=252
x=252/4
x=63 is the smallest integer.
61+2=65 for the middle integer.
61+4=67 is the largest integer.
Proof:
67^2=65^2+264
4,489=4,225+264
4,489=4,489
|
Pythagorean-theorem/162719: a mover must put a circular mirror two meters in diameter through a one meter by 1.8 meter doorway. find the lenght of the diagonal of the doorway. will the mirror fit?
please help:)! 1 solutions
Answer 119932 by checkley77(12569) on 2008-10-17 21:49:35 (Show Source):
|
Polynomials-and-rational-expressions/162581: heres another.
i dont get it when there on each side of the equal sign
-2(x+11)=-x+10
oh and
3(y+6)=2y+14
and i have to check which i also dont understand!
1 solutions
Answer 119823 by checkley77(12569) on 2008-10-16 19:50:26 (Show Source):
You can put this solution on YOUR website!-2(x+11)=-x+10
-2x-22=-x+10
-2x+x=10+22
-x=32 answer.
x=-32
Proof:
-2(-32+11)=-(-32)+10
-2*-21=32+10
42=42
--------------------------------
3(y+6)=2y+14
3y+18=2y+14
3y-2y=14-18
y=-4 answer.
Proof:
3(-4+6)=2(-4)+14
3*2=-8+14
6=6
|
Numeric_Fractions/162549: A can of cola costs x pence.
An ice cream costs y pence.
Atif buys 3 cans of cola and 2 ice creams.
Write down an expression, in terms of x and y, for the total cost, in pence.
1 solutions
Answer 119822 by checkley77(12569) on 2008-10-16 19:43:53 (Show Source):
|
Miscellaneous_Word_Problems/162550: It took Betsy 10 min more to walk home from school than it took him to walk to school from home. If his total walking time from home to school and back again was 54 min, how long did it take him to walk to school?
-please show in an algebraic equation. 1 solutions
Answer 119821 by checkley77(12569) on 2008-10-16 19:41:42 (Show Source):
|
Equations/162572: This question is from textbook math makes sence
9.jason works at a fish and chips resoront. he earns $7/h during a week, and$9/h on the weekend
a)jason works8 h during the week and 5 h on the weekend. write an expression for his earnings. 1 solutions
Answer 119817 by checkley77(12569) on 2008-10-16 19:30:39 (Show Source):
|
Numbers_Word_Problems/162575: Find four consecutive odd integers have a sum of 120. What are the integers? 1 solutions
Answer 119814 by checkley77(12569) on 2008-10-16 19:26:47 (Show Source):
You can put this solution on YOUR website!let x, x+2, x+4, x+6 be the 4 integers.
x+x+2+x+4+x+6=120
4x+12=120
4x=120-12
4x=108
x=108/4
x=27 for the first integer.
27+2=29 for the next one.
27+4=31 for the next.
27+6=33 for the largest.
Proof:
27+29+31+33=120
120=120
|
Matrices-and-determiminant/162569: Question 162554: 9. (4, -10), (1, -1)
x y 1 x y
4 -10 1 4 -10
1 -1 1 1 -1
(x)(-10)(1)+(y)(1)(1)+(1)(4)(-1)+(1)(-10)(1)-(-1)(1)(x)-(1)(4)(y)=
-10x+y+(-4)-(-10)-(-x)-4y=
-9x-3y+6=0
-9x-3y=-6
-3y+(-9x)=-6
-3y=-6+9x
-y=2+3x
Y=-3x-2
Can you find my sign error? Im sure im just overlooking something,but I can't find it. Thank you so much!
checkley77 was nice enough to try to help me,but im still confused. I see that instead of (x)(-10)(1)+(y)(1)(1)+(1)(4)(-1)+(1)(-10)(1)-(-1)(1)(x)-(1)(4)(y)=
I needed to have (x)(-10)(1)+(y)(1)(1)+(1)(4)(-1)-(1)(-10)(1)-(-1)(1)(x)-(1)(4)(y)=
But I want to know if that effects my answer? Is Y=-3x-2 correct? 1 solutions
Answer 119810 by checkley77(12569) on 2008-10-16 19:19:49 (Show Source):
You can put this solution on YOUR website!I needed to have (x)(-10)(1)+(y)(1)(1)+(1)(4)(-1)-(1)(-10)(1)-(-1)(1)(x)-(1)(4)
-10x+y+(-4)-(-10)-(-x)-4y=0
this becomes:
-10x+y-4+10+x-4y=0
-3y-9x+6=0
-3y=9x-6
y=9x/-3-6/-3
(y)=-3x+2
But I want to know if that effects my answer? Is Y=-3x-2 correct.
I assumed you would complete the solution after the correction was provided??????
|
|