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Question 519279: Marco invests his summer earnings of $2440. He invests part of the money at 8% per year and the rest at 7.5% per year. After one year these investments earned $193 in simple interest. How much did Marco invest at each rate?
My solution also has to have "let" statements.
Click here to see answer by mananth(16946)

Question 519421: Peggy paid $51.30 for 2 boxes of chocolates, 6 roses, and 3 greeting cards. Joe paid $72.05 for 3 boxes of chocolates, 12 roses, and 2 greeting cards. If 1 greeting card costs the same as 2 roses, how much does a box of chocolates cost
Click here to see answer by mananth(16946)

Question 519669: Solve using substitution:
3x+5y =-6 ; x=5y+3
I have solved that Y= 3/4 but im not sure what to do with the fraction to figure x out. Thank You. Angela

Click here to see answer by jim_thompson5910(35256)

Question 519722: x+y=3
x-y=5
Click here to see answer by jim_thompson5910(35256)

Question 519722: x+y=3
x-y=5
Click here to see answer by oberobic(2304)

Question 519824: What is
It is the pathagoream theorum by the way.
Click here to see answer by Alan3354(69443)

Question 519885: i dont understand how to write an equation for the line that is parallel to y=(4/3)x-7 ; and contains given point, (7,2).
Click here to see answer by rfer(16322)

Question 519885: i dont understand how to write an equation for the line that is parallel to y=(4/3)x-7 ; and contains given point, (7,2).
Click here to see answer by mananth(16946)

Question 519885: i dont understand how to write an equation for the line that is parallel to y=(4/3)x-7 ; and contains given point, (7,2).
Click here to see answer by stanbon(75887)

Question 519890: One number is 62 more than another number. If twice the greater number is subtracted from five times the lesser number, the result is 155. What are the two numbers?
Click here to see answer by mananth(16946)

Question 520377: How would you write a system of equations to find the concentration of salt in solution A and B when 3mm of solution A are mixed with 3mm of solution B and the result is a 40% salt solution, and when 4mm of solution A are mixed with 2mm of solution B and the result is a 35% salt solution?
I was thinking 3x+3y=.4; 4x+2y=.35 but it doesn't seem right?
I would be very appreciative if someone could help me thank you!
Click here to see answer by scott8148(6628)

Question 520446: Assume that the number of defective basketballs produced is related by a linear equation to the total number produced. Suppose that 10 defective balls are produced in a lot of 325, and 17 defective balls are produced in a lot of 450. Find the number of defective balls produced in a lot of 550 balls.
Click here to see answer by josmiceli(19441)

Question 520541: x-y+9z=-27
2x-4y-z=-1
3x+6y-3z=27
I have tried and tried on this problem for an hour and have gotten different answers each time. All I need to know is what are the values of x, y, and z?
Thank you.
Click here to see answer by scott8148(6628)

Question 520699: Pratap Puri rowed 18 miles down the Delaware River in 2 hours, but the return trip took him 4 1/2 hours. Find the rate Pratap can row in still water, and find the rate of the current.
Let x= rate Pratap can row in still water and y = rate of the current
Downstream x+y
Upstream x-y
I think the first one is 2x+y=18
I can't figure out the second part. Something like:
x=y-4.5.

Click here to see answer by mananth(16946)

Question 520985: i would like it if you could check my answers on turning point slope form into standard form. the original problem was this: y+5=-5(x-3)i got: 5x+y=10
problem: y-10=-2(x-3) i got: 2x+y=16 problem: y-2=-1/2(x-4) i got: 1/2x+y=4
please check,if they are wrong can you correct. thanks
Click here to see answer by lwsshak3(11628)

Question 521313: How would I solve y = 15 - 3x and 7y + 3x = 15 using the substitution method? I tried plugging the y = 15 - 3x for the y but I came up with a decimal answer and I don't think it's supposed to be a decimal?
Click here to see answer by mananth(16946)

Question 521318: Hello, I am working on the problem 9x + 3y - 5 = 0 and 3x + y = 5/3. It's asking to solve the system of equations using substitution. I don't get what I have to plug in to get the answer?
Click here to see answer by mananth(16946)

Question 520995: find the solution of the system y=x^2+5 y=2x+4
Click here to see answer by umnikmo(75)

Question 521832: y+5x=0
x+y=12
how do you do this? please show all steps

Click here to see answer by umnikmo(75)

Question 521832: y+5x=0
x+y=12
how do you do this? please show all steps

Click here to see answer by oberobic(2304)

Question 521829: 2.00x+1.5y=550.00
x=3y-100
i need to graph so im guessing it needs to be in slope intercept form? i keep getting decimals and i need help
Click here to see answer by oberobic(2304)

Question 521970: the length of a rectangle is 7 meters less than twice he width. If the perimeter is 40 meters, find the dimensions of the rectangle.
Click here to see answer by mananth(16946)

Question 522095: if x + 3y + 2z = 48 and 2x + 3y + 4z = 69, then the value of 3x + 3y + 6z is

Click here to see answer by Edwin McCravy(20056)

Question 522071: A challenge for us, maybe not for you!!!!
how to develop the following:
3power of X = 3 power of x-1 + 7
Click here to see answer by richard1234(7193)

Question 522240: I need help solving this problem
Solve the system by back substitution
3x - 2y - 4z + 2w = 6
2y + 5z - 3w = 7
3z -4w = 0
3w = 15
Click here to see answer by umnikmo(75)

Question 522228: I need help solving this problem
2x + 2y - 4z + w = -5
3y + 4z - w = 0
2z -7w = -6
5w = 15
Click here to see answer by richwmiller(17219)

Question 522786: Solve this system using elimination. If a single solution exists, write the solution as an ordered pair. Your answer will be an ordered pair, no solution, or infinitely many solutions.2x-y=0 and 3x+y=5

Click here to see answer by stanbon(75887)

Question 522782: Solve this system using elimination. If a single solution exists, write the solution as an ordered pair. Your answer will be an ordered pair, no solution, or infinitely many solutions.
Click here to see answer by richard1234(7193)

Question 522860: 6x-5y=-67
7x+83=y
7m+n=13
m-9n=11
4x+5y=15
-6x+y=37
6x+9y=-33
-3x+y=22
Im suppose to solve using the substition method, I am confused!
Click here to see answer by stanbon(75887)

Question 522286: 3x+7-7y+2x-3y-1 what is that equation?
Click here to see answer by richard1234(7193)

Question 523223: what is the standard form of the equation of the line passing through the point (-2,-2) and perpindicular to the line 3x-5y=-5 ?
Click here to see answer by Maths68(1474)

Question 523539: I need help with linear expressions
-3(2s-5)-15=-3(5s+0)-5
Click here to see answer by rfer(16322)

Question 523549: Hi everyone, I'm stuck on this problem, if someone could I help I would really appreciate it. Thank you :)
The difference between three times a number and another is 2. Their sum is 6. Write a system of equations. Then solve for the numbers by graphing the equations.

I can graph the equation, I'm stuck on figuring out the equation. Thanks!
Click here to see answer by Alan3354(69443)

Question 523644: the line has a slope of -2/3 and passes through (6,12)
Click here to see answer by nerdybill(7384)

Question 523644: the line has a slope of -2/3 and passes through (6,12)
Click here to see answer by oberobic(2304)

Question 523807: solve the following system of equations using the elimination method:
3x+2y=48
9x-8y=-24
Click here to see answer by Maths68(1474)

Question 523977: solve the following system using the substitution method:
y=3x-2
15x-5y=10
Click here to see answer by solver91311(24713)

Question 524081: A sales representative informs you that there are 56 houses for sale with two floor plans still available. Use x to represent floor plan one and y to represent floor plan two. Write an equation that illustrates the situation.

Later, the sales representative indicates that there are three times as many homes available with the second floor plan than the first. Write an equation that illustrates this situation. Use the same variables used in previous problem.
I know that the first part of the solution is x + y = 56, but after that, I get confused. Please help
Click here to see answer by josmiceli(19441)

Question 524127: The problem asks to solve the system using the substitution method. The equations are: -2x+y=6 and 4x-2y=5. In the book this is number 12, since they only show the answers in the back of the book to the odd numbers I did number 11. I got that right but I can't figure this one out. Could you please show me the steps to doing this problem. Thank you.
Click here to see answer by ankor@dixie-net.com(22740)

Question 524158: Classify the system without solving.
2x+3y=12
x+y=4
Click here to see answer by stanbon(75887)

Question 524215: solve the system of equations by graphing.
3x-18=9y
2x-6y=-12
Click here to see answer by mananth(16946)

Question 524256: determine the set of values of k for which the line 2y=x+k does not intersect the curve y=x^2-4x+7
Click here to see answer by stanbon(75887)

Question 524408: solve using the addition method
x+y=10
x-y=8
Click here to see answer by nerdybill(7384)

Question 524601: I honestly do not know where to begin on this one. I looked in the textbook for an example and could not find one for this setup.
Word problem in a form of a Linear equation.
PROBLEM: For a summer job, Dwayne decides to sell magazine subscriptions. He will be paid $18 a day plus $1 for each subscription he sells. If he works for 25 days and makes $574, how many subscriptions did he sell?
Click here to see answer by richwmiller(17219)

Question 524620: how can i find the slope and y-intercept for 4y+14.2=2.4x-2.6
Click here to see answer by Alan3354(69443)

Older solutions: 1..45, 46..90, 91..135, 136..180, 181..225, 226..270, 271..315, 316..360, 361..405, 406..450, 451..495, 496..540, 541..585, 586..630, 631..675, 676..720, 721..765, 766..810, 811..855, 856..900, 901..945, 946..990, 991..1035, 1036..1080, 1081..1125, 1126..1170, 1171..1215, 1216..1260, 1261..1305, 1306..1350, 1351..1395, 1396..1440, 1441..1485, 1486..1530, 1531..1575, 1576..1620, 1621..1665, 1666..1710, 1711..1755, 1756..1800, 1801..1845, 1846..1890, 1891..1935, 1936..1980, 1981..2025, 2026..2070, 2071..2115, 2116..2160, 2161..2205, 2206..2250, 2251..2295, 2296..2340, 2341..2385, 2386..2430, 2431..2475, 2476..2520, 2521..2565, 2566..2610, 2611..2655, 2656..2700, 2701..2745, 2746..2790, 2791..2835, 2836..2880, 2881..2925, 2926..2970, 2971..3015, 3016..3060, 3061..3105, 3106..3150, 3151..3195, 3196..3240, 3241..3285, 3286..3330, 3331..3375, 3376..3420, 3421..3465, 3466..3510, 3511..3555, 3556..3600, 3601..3645, 3646..3690, 3691..3735, 3736..3780, 3781..3825, 3826..3870, 3871..3915, 3916..3960, 3961..4005, 4006..4050, 4051..4095, 4096..4140, 4141..4185, 4186..4230, 4231..4275, 4276..4320, 4321..4365, 4366..4410, 4411..4455, 4456..4500, 4501..4545, 4546..4590, 4591..4635, 4636..4680, 4681..4725, 4726..4770, 4771..4815, 4816..4860, 4861..4905, 4906..4950, 4951..4995, 4996..5040, 5041..5085, 5086..5130, 5131..5175, 5176..5220, 5221..5265, 5266..5310, 5311..5355, 5356..5400, 5401..5445, 5446..5490, 5491..5535, 5536..5580, 5581..5625, 5626..5670, 5671..5715, 5716..5760, 5761..5805, 5806..5850, 5851..5895, 5896..5940, 5941..5985, 5986..6030, 6031..6075, 6076..6120, 6121..6165, 6166..6210, 6211..6255, 6256..6300, 6301..6345, 6346..6390, 6391..6435, 6436..6480, 6481..6525, 6526..6570, 6571..6615, 6616..6660, 6661..6705, 6706..6750, 6751..6795, 6796..6840, 6841..6885, 6886..6930, 6931..6975, 6976..7020, 7021..7065, 7066..7110, 7111..7155, 7156..7200, 7201..7245, 7246..7290, 7291..7335, 7336..7380, 7381..7425, 7426..7470, 7471..7515, 7516..7560, 7561..7605, 7606..7650, 7651..7695, 7696..7740, 7741..7785, 7786..7830, 7831..7875, 7876..7920, 7921..7965, 7966..8010, 8011..8055, 8056..8100, 8101..8145, 8146..8190, 8191..8235, 8236..8280, 8281..8325, 8326..8370, 8371..8415, 8416..8460, 8461..8505, 8506..8550, 8551..8595, 8596..8640, 8641..8685, 8686..8730, 8731..8775, 8776..8820, 8821..8865, 8866..8910, 8911..8955, 8956..9000, 9001..9045, 9046..9090, 9091..9135, 9136..9180, 9181..9225, 9226..9270, 9271..9315, 9316..9360, 9361..9405, 9406..9450, 9451..9495, 9496..9540, 9541..9585, 9586..9630, 9631..9675, 9676..9720, 9721..9765, 9766..9810, 9811..9855, 9856..9900, 9901..9945, 9946..9990, 9991..10035, 10036..10080, 10081..10125, 10126..10170, 10171..10215, 10216..10260, 10261..10305, 10306..10350, 10351..10395, 10396..10440, 10441..10485, 10486..10530, 10531..10575, 10576..10620, 10621..10665, 10666..10710, 10711..10755, 10756..10800, 10801..10845, 10846..10890, 10891..10935, 10936..10980, 10981..11025, 11026..11070, 11071..11115, 11116..11160, 11161..11205, 11206..11250, 11251..11295, 11296..11340, 11341..11385, 11386..11430, 11431..11475, 11476..11520, 11521..11565, 11566..11610, 11611..11655, 11656..11700, 11701..11745, 11746..11790, 11791..11835, 11836..11880, 11881..11925, 11926..11970, 11971..12015, 12016..12060, 12061..12105, 12106..12150, 12151..12195, 12196..12240, 12241..12285, 12286..12330, 12331..12375, 12376..12420, 12421..12465, 12466..12510, 12511..12555, 12556..12600, 12601..12645, 12646..12690, 12691..12735, 12736..12780, 12781..12825, 12826..12870, 12871..12915, 12916..12960, 12961..13005, 13006..13050, 13051..13095, 13096..13140, 13141..13185, 13186..13230, 13231..13275, 13276..13320, 13321..13365, 13366..13410, 13411..13455, 13456..13500, 13501..13545, 13546..13590, 13591..13635, 13636..13680, 13681..13725, 13726..13770, 13771..13815, 13816..13860, 13861..13905, 13906..13950, 13951..13995, 13996..14040, 14041..14085, 14086..14130, 14131..14175, 14176..14220, 14221..14265, 14266..14310, 14311..14355, 14356..14400, 14401..14445, 14446..14490, 14491..14535, 14536..14580, 14581..14625, 14626..14670, 14671..14715, 14716..14760, 14761..14805, 14806..14850, 14851..14895, 14896..14940, 14941..14985, 14986..15030, 15031..15075, 15076..15120, 15121..15165, 15166..15210, 15211..15255, 15256..15300, 15301..15345, 15346..15390, 15391..15435, 15436..15480, 15481..15525, 15526..15570, 15571..15615, 15616..15660, 15661..15705, 15706..15750, 15751..15795, 15796..15840, 15841..15885, 15886..15930, 15931..15975, 15976..16020, 16021..16065, 16066..16110, 16111..16155, 16156..16200, 16201..16245, 16246..16290, 16291..16335, 16336..16380, 16381..16425, 16426..16470, 16471..16515