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Linear-equations/333321: This is a silly question, but I'm in doubt for trying to resolve (6v+3)(6v+3). I found it 6v^2+36v+9. Can I simplify this dividing by 3, to 2v^2+12v+3? 1 solutions Answer 238832 by mananth(12270)   on 2010-08-20 02:08:53 (Show Source): You can put this solution on YOUR website! (6v+3)(6v+3) = 36v^2+36v+9 ( it is not 6v^2) =9(4v^2+4v+1) =9(2v+1)^2

Finance/333317: A house purchased for $125,000 is expected to appreciate according to the formula y = 7500x + 125000, where y is the value of the house after x years. Find the value of the house 10 years later 1 solutions Answer 238831 by mananth(12270)   on 2010-08-20 02:03:51 (Show Source): You can put this solution on YOUR website! y = 7500x + 125000, y= 7500*10 +125,000 y= 75000+125000 y= $ 200,000

Finance/333316: Two cars leave Pima Community College traveling in opposite directions. One car travels at 80 mph and the other at 54 mph. In how many hours will they be 938 miles apart? 1 solutions Answer 238830 by mananth(12270)   on 2010-08-20 02:00:58 (Show Source): You can put this solution on YOUR website! One car travels at 80 mph and the other at 54 mph. In how many hours will they be 938 miles apart? .. they are travelling in opposite directions the effective speed is 80+54 = 134 mph distance = 938 miles .. Time when they will be 938 miles apart will be 938/134 = 7 hours

Volume/333296: If the volume of an orange is 523.3 cubic cm, what would be the edible volume of the orange if the peel is 0.5 cm thick? What would be the percent of edible orange? 1 solutions Answer 238829 by mananth(12270)   on 2010-08-20 01:56:38 (Show Source): You can put this solution on YOUR website! volume with peel = 523.3 cu.cm volume of sphere = r= 5 cm ... The peel is 0.5 cm thick the diameter of of edible orange will be 5-1 cm = 4cm .. Volume edible part = = 268 cu. cm ... percent of edible volume = (268/523.3)*100 = 51.21 %

Numbers_Word_Problems/333301: suppose a video store charges non-members $3 to rent a video. a membership cost $21 and then each video costs only $1.50 to rent. how many videos would you need to rent in order to justidy a membership? 1 solutions Answer 238827 by mananth(12270)   on 2010-08-20 01:17:51 (Show Source): You can put this solution on YOUR website! non-members $3 to rent a video. a membership cost $21 and then each video costs only $1.50 to rent. .. Let number of videos to be rented be x 21+1.5x < 3x add -1.5x 21+1.5x-1.5x<3x-1.5x 21< 3x-1.5x divide by 1.5 21/1.5 x> 14 For x > 14 membeship would be a better deal

Travel_Word_Problems/333302: A boat travels 10km upstream and 10km back. The time for the roundtrip is 5 hours. The speed of the stream is 2km/hour. What is the speed of the boat in still water? 1 solutions Answer 238825 by mananth(12270)   on 2010-08-20 01:03:53 (Show Source): You can put this solution on YOUR website! let the speed of the boat in still water be x kmph speed of current =2kmph .. speed downstream = x+2 speed upstream = x-2 .. distance both ways = 10 km time = distance / speed .. time upstream + time downstream = 5 hours 10/(x+2)+10/(x-2) = 5 LCM = (x+2)(x-2) 10(x-2)+10(x+2) / (x-2)(x+2)= 5 10x-20+10x+20=5(x-2)(x+2) 20x=5x^2-20 5x^2-20x-20=0 divide by 5 x^2-4x-4=0 .. solve by quadratic equation formula x= (-b+-sqrt(b^2-4ac))/2a a=1,b=-4,c=-4 b^2-4ac = 16+16=32 x1=(4+sqrt32) /2 x1= 4.82 kmph .. x2=(4-sqrt32) /2 x2= -0.82 ( Ignore) the speed of boat in still water = 4.82 km/h

Age_Word_Problems/333303: My age today is three times what it will be three years from now, minus three times what my age was three years ago. How old am I? i want explianation 1 solutions Answer 238821 by mananth(12270)   on 2010-08-20 00:38:08 (Show Source): You can put this solution on YOUR website! let my age be x years now. my age after 3 years (x+3) my age 3 years ago (x-3) .. x= 3(x+3)-3(x-3) x=3x+9-3x+9 x=18 years my age now

Travel_Word_Problems/333276: a hiker hikes up a mountain 1 mi/h slower than she hikes down the mountain. if it takes her 1.5 hours to hike up the mountain, and only 1 hour to hike down it, how fast does she movein each direction? 1 solutions Answer 238815 by mananth(12270)   on 2010-08-20 00:17:50 (Show Source): You can put this solution on YOUR website! a hiker hikes up a mountain 1 mi/h slower than she hikes down the mountain. if it takes her 1.5 hours to hike up the mountain, and only 1 hour to hike down it, how fast does she movein each direction? .. let speed down the mountain be x mph up the mountain speed = x-1 mph. .. time down the mountain = 1 hour time up the mountain = 1.5 hours .. Distance up & down is the same. .. distance = speed * time 1*x= (x-1)*1.5 x=1.5x-1.5 1.5x-x = 1.5 0.5x = 1.5 x= 1.5/0.5 x = 3 mph speed down the mountain. 3-1 = 2mph speed up the mountain.

Inequalities/333286: -n+2-4n>7 1 solutions Answer 238808 by mananth(12270)   on 2010-08-19 22:54:58 (Show Source): You can put this solution on YOUR website! -n+2-4n>7 -5n+2>7 add -2 -5n+2-2>7-2 -5n>5 divide by -5 -5n/-5 < 5/-5 n<-1

Money_Word_Problems/333277: three shirts and 2 pants cost $50. two shirts and 3 pants cost $80. what is the cost of one shirt and one pants? 1 solutions Answer 238807 by mananth(12270)   on 2010-08-19 22:52:10 (Show Source): You can put this solution on YOUR website! three shirts and 2 pants cost $50. two shirts and 3 pants cost $80. .. let shirt cost $x & pants cost $y .. 3x+2y=50..............1 2x+3y=80..............2 .. multiply equation 1 by -2 & equation 2 by 3 to eliminate x .. -2(3x+2y)+3(2x+3y)= -2*50+3*80 -6x-4y+6x+9y=-100+240 +5y=140 y=$28 cost of pants plug value of y in equation 1 3x+2y=50 3x+2*28=50 3x+56=50 3x=-6 x=-2 . X cannot be negative . However cost of 1 Pant and 1 shirt = $26 ( mathematically)

Travel_Word_Problems/333278: You drive at a constant speed of 48 miles per hour.How far do you travel in 2 hours? 1 solutions Answer 238806 by mananth(12270)   on 2010-08-19 22:38:46 (Show Source): You can put this solution on YOUR website! Speed = 48mph time = 2hours .. Distance = speed * time Distance = 48*2 distance = 96 miles

Distributive-associative-commutative-properties/333279: i need help on this equation but first it says use the distributive property the equation is (-8z-10)(-1.5) 1 solutions Answer 238804 by mananth(12270)   on 2010-08-19 22:37:12 (Show Source): You can put this solution on YOUR website! (-8z-10)(-1.5) .. -1.5*(-8z)-(-1.5)(10) 12z+15

Finance/333280: Deposit $120 in a savings account that pays an annual interest rate of 2.5%. How much simple interest would you earn in 2 years? I=Prt I=(120)(0.025)(2) I=6 2 years interest on $120 at a rate of 2.5%. Is this correct? 1 solutions Answer 238803 by mananth(12270)   on 2010-08-19 22:32:57 (Show Source): You can put this solution on YOUR website! I = P*r*t P=120 r= 2.5% = 0.025 t=2 .. I=120*0.025*2 I=$6 You were right

test/333281: Solve by factoring. M^2- 9=0 1 solutions Answer 238802 by mananth(12270)   on 2010-08-19 22:26:48 (Show Source): You can put this solution on YOUR website! M^2- 9=0 .. M^2+3M-3M-9=0 M(M+3)-3(M+3)=0 (M+3)(M-3)=0 M= +/- 3 ..

Equations/333284: 2-6(y+1)=4(2-3y)+6 2-6y+6=8-12y+6 -6y+12y=2+8+6 6y=16 1 solutions Answer 238800 by mananth(12270)   on 2010-08-19 22:24:03 (Show Source): You can put this solution on YOUR website! 2-6(y+1)=4(2-3y)+6 2-6y-6=8-12y+6 -6y+12y=-2+8+6 6y=12 divide by 6 y=2

Exponents/333282: What is (-2)WITH AN EXPONENT OF 4.And how do you slove it? 1 solutions Answer 238799 by mananth(12270)   on 2010-08-19 22:21:03 (Show Source): You can put this solution on YOUR website! = 16. any negative number raised to a positive index is always positive

Graphs/333260: In graphing a system with two or more inequalities, how do you show the solution on the graph 1. graph each curve as a dotted or solid line 2. test a random point from one of the regions 3.shade in the x-axis to show the x-values whose points satisfy each inequality 4. Look for the region that was shaded as the solution for each inequality in the system Please help. 1 solutions Answer 238790 by mananth(12270)   on 2010-08-19 20:44:05 (Show Source): You can put this solution on YOUR website! No 4. look for the shaded portion common to both solutions.

Radicals/332891: multiply and simplify. assume all variables represent nonnegative real numbers.Write anwswer in radical notation. can you please help me to do this problem, I do not understand this at all. thank you 1 solutions Answer 238614 by mananth(12270)   on 2010-08-19 04:40:23 (Show Source): You can put this solution on YOUR website! .. .. .. ..

Numbers_Word_Problems/332937: If the first and third of three consecutive odd integers are added, the result is 69 less than five times the second integer. Find the third integer. I dont understand how to solve this problem or even how to set problem up 1 solutions Answer 238613 by mananth(12270)   on 2010-08-19 04:23:06 (Show Source): You can put this solution on YOUR website! let the odd integers be x,x+2,x+4 .. x+x+4 =5(x+2)-69 2x+4=5x+10-69 2x+4=5x-59 add -4 to both sides 2x+4-4=-59-4+5x 2x=-63+5x add -5x to both sides 2x-5x= 63+5x-5x -3x=-63 divide by -3 -3x/-3 = -63/-3 x=21 the numbers are 21, 23, 25 CHECK 21+25 = 5*(23)-69 46=115-69 46=46

Surface-area/333001: A cube has a surface area of 240 cm^2 . What is the length of one side? 1 solutions Answer 238612 by mananth(12270)   on 2010-08-19 03:51:36 (Show Source): You can put this solution on YOUR website! L*L = l^2 = surface area of 1 side there are 6 sides to a cube 6L^2= 240 divide by 6 6L^2/6 = 240/6 L^2= 40 L = sqrt 40

Numbers_Word_Problems/332941: the square root of the difference of two is 5. the sum of the two number is 31 what are the two numbers? 1 solutions Answer 238611 by mananth(12270)   on 2010-08-19 03:48:38 (Show Source): You can put this solution on YOUR website! let the numbers be x &y sqrt(x-y)=5 take square x-y = 25 x+y=31 .. add the two equations to eliminate y 2x= 56 divide by 2 x= 28 .. plug value of x in equation x+y=31 28+y=31 y = 31-28 y=3

Graphs/332972: M=-9(2,4) Find a equation line 1 solutions Answer 238610 by mananth(12270)   on 2010-08-19 03:20:37 (Show Source): You can put this solution on YOUR website! M= slope = -9 point (2,4) general equation y= mx+b plug value of x and y to get value of b 4=-9*2+b 4=-18+b add 18 to both sides 4+18-18+18+b b=22 so the equation will be y= -9x +22 ..

Inequalities/332987: At 10:30am two planes leave Houston, one flying east at 560km/h and the other flying west at 640km/h. At what time will they be 2100km apart? 1 solutions Answer 238609 by mananth(12270)   on 2010-08-19 03:12:21 (Show Source): You can put this solution on YOUR website! one plane speed = 560 km/h other plane speed = 640km/h .. they are travelling in opposite directions so effective speed = 560+640= 1200 km/h .. distance = 2100 speed = 1200 km/h time = distance /speed time 2100/1200 = 1.75 hours = 1 hour 45 minutes they left at 10.30 am. add 1 hour 45 minutes 12.15 pm. the time they will be 2100 km apart CHECK (7/4 * 640)+(7/4 * 560) = 2100 km

Sequences-and-series/332996: if interest is compounded annually, how long does it take $1,000 to double at 8% interest? 1 solutions Answer 238608 by mananth(12270)   on 2010-08-19 02:37:55 (Show Source): You can put this solution on YOUR website! A=P(1+(r/100))^n 2000=1000*(1+0.08)^n divide by 1000 2000/1000 = 1.08^n 2= 1.08^n take log on both sides log 2 = n*log 1.08 divide by log (1.08) log2/log 1.08 = n n = 9 years

Equations/332998: What does h equal and how do you write it out to solve the problem? 1 solutions Answer 238607 by mananth(12270)   on 2010-08-19 02:28:25 (Show Source): You can put this solution on YOUR website! 19=4h+20+h 19=5h+20 add-20 to both sides 19-20=5h+20-20 -1= 5h divide by 5 -1/5 = 5h/5 -1/5 = h

Percentage-and-ratio-word-problems/332995: what is the ratio of 2 3/4 to 6 1/4 1 solutions Answer 238606 by mananth(12270)   on 2010-08-19 02:23:59 (Show Source): You can put this solution on YOUR website! 2 3/4 to 6 1/4 ... ... ... =

test/332988: The sum of four consecutive integers is 1344. Find all four integers. 1 solutions Answer 238603 by mananth(12270)   on 2010-08-19 01:12:05 (Show Source): You can put this solution on YOUR website! Let the 4 integers be x,x+1,x+2,x+3 .. The sum = 1334 ( I have changed 1344 to 1334) x+x+1+x+2+x+3=1334 4x+6 = 1334 add -6 to both sides 4x+6-6 =1328-6 4x=1328 divide by 4 4x/4 = 1328/4 x= 332 the integers are 332,333,334,335

Quadratic_Equations/332783: college algebra use an equality and the five step process to solve the problem translate reword carry-out check state dg's plumbing and heating charges $50 plus $65 per hour for emergency service. Bill remembers being billed just over $450 for an emergency call. how long to the nearest hour was the plumber at bill's house? 1 solutions Answer 238439 by mananth(12270)   on 2010-08-18 10:52:12 (Show Source): You can put this solution on YOUR website! dg's plumbing and heating charges $50 plus $65 per hour billing $450 . .. let the number of hours worked be $x 50+65x= 450 add -50 to both sides 50-50+65x=450-50 65x=400 divide by 65 65x/65 = 400/65 x= 6.15 hours so plumber worked for about 6 hours .. CHECK 50+6.15*65 = $449.75

Matrices-and-determiminant/332777: multiply both side of the equation by a common denominator to eliminate the fractions. Then solve the system. x/4+3y=31 2x-y/5=8 I have been struggling to try to solve this for over 4 days now and have had no luck. We are given the final answer which is (5,10) but I can not figurge out how they got to that. I need to show the work and solve the problem. Can someone please help me. 1 solutions Answer 238438 by mananth(12270)   on 2010-08-18 10:40:46 (Show Source): You can put this solution on YOUR website! while writing the problem it is advisable to put brackets to get clarity. x/4+3y=31 ...............1 2x-y/5=8 ................2 ... multiply by 4 4*x/4 +4*3y= 31*4 x+12y=124...........3 .. 2x- y/5 =8 multiply by 5 5*2x-5*y/5= 5*8 10x-y= 40.............4 .. .. multiply equation 3 by -10 and to equation 4 -10x-120y+10x-y=-1240+40 -121y=-1200 y= 1200/121 plug the value of y in the above equation x=604/121

Radicals/332762: hello please help me . I am a bit confused about radicals and how to solve them. In this math packet of mine it says "put into simplified radical form- no decimals!" and it shows problems with (24) 24 being the radicand, 3(50) 50 as a radicand and (17). please help me if you can and if it wouldn't be too much trouble explain to me how you got this answer i am very confused 1 solutions Answer 238437 by mananth(12270)   on 2010-08-18 10:10:42 (Show Source): You can put this solution on YOUR website! I fail to understand your confusion. A radicand is the number or term which is inside the radical sign. Here the radicand is 50, the square root sign is the radical if you are asked to simplify 2 is the radicand ... find the radicand of sqrt98* sqrt54 .. 3 is the radicand Hope you get it.

Travel_Word_Problems/332717: sam drove 500km from city A to City B in 5.5hr. he drove part of the way at 100km/h and the rest of the way at 80km/h. how far did he drive at each speed? 1 solutions Answer 238423 by mananth(12270)   on 2010-08-18 06:30:03 (Show Source): You can put this solution on YOUR website! total distance = 500 km .. he drove x km at 100 km/h 500-x at 80 km/h .. time he drove at 100 = x/100 time he drove at 80 = (500-x)/ 80 .. total time he drove = 5.5 hours = 11/2 hours .. x/100+(500-x)/80 = 11/2 8x+10(500-x) / 800 = 11/2 8x+5000-10x / 800 = 11/2 -2x+5000 / 800 = 11/2 2(-2x+5000)= 11*800 -4x+10000=8800 -4x=-10000+8800 -4x=-1200 x=-1200/-4 x=300 km. the distance he drove at 100km/h Balance 200 km he drove at 80 km/h