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Question 271186: 1 number is 4 less than 3 times another. If their sum is increased by 5, the result is 25. Find the numbers.
The numbers are 6 & 14 - how did they get 6, I can figure out 14 but missing an essential part.
Thank you.
Click here to see answer by meow123(2)

Question 271155: A store owner has two different blends of coffee. Brand A sells for $10.50/lb and Brand B sells for $5.75/lb. The owner wants to create a 25 lb mixture of Brand A and B to sell for $8.22 a pound. How much of each blend should he use?
Click here to see answer by josmiceli(9698)

Question 271456: 2x+y=12, 3x-y=13
How do you solve this equation for x and y?
Click here to see answer by scott8148(6628)

Question 271575: A steamboat went 8 miles upstream in 1 hour. The return trip took only 30 minutes. Assume that the speed of the current and the direction were constant during both parts of the trip. Find the speed of the boat in still water and the speed of the current.
Please help me figure out what 2 equations I would use and then I believe I can get the answer.
Thanks in advance for your help!
Click here to see answer by stanbon(57424)

Question 271657: 3x+5y=-6, 3x-15/2y=-9
Click here to see answer by checkley77(12569)

Question 271709: solve by substitution
3m + n =1
m - 4n = 9
Click here to see answer by LarissaRichardson(34)

Question 271707: solve by elimmination method
6x - 9y = 25.5
7y - 2x = -10.5
Click here to see answer by Tobiasz(54)

Question 271706: solve by elimination
5x + 5y = -13
7x - 2y = 17
Click here to see answer by Tobiasz(54)

Question 271706: solve by elimination
5x + 5y = -13
7x - 2y = 17
Click here to see answer by Alan3354(30993)

Question 271708: solve by elimination method
0.3x - 0.2y = 4
0.4x + 0.5y = 63/19
Click here to see answer by Tobiasz(54)

Question 271804: You plant a 14 inch hemlock tree in your back yard that grows at a rate of 4 inches per year and an 8 inch blue spuce tree that grows at a rate of 6 inches per year. In how many years after you plant the trees will the two trees be the same height? And how tall will they be?
I have tried the following:
4x + 6y = 365
x + y = 2

Click here to see answer by scott8148(6628)

Question 271870: 6-4(-6x+8)=7(-3x-3)+7
Click here to see answer by LarissaRichardson(34)

Question 272066: Please solve this using the elimination method.
2x + 3y = 2
-28 = 4x - 2y

Click here to see answer by checkley77(12569)

Question 272065: Please solve this using the elimination method.
9x + 2y = 2
21x + 6y = 4
Click here to see answer by checkley77(12569)

Question 272064: Please solve this using the substitution method.
x = 3y - 5
6x - 18y = -30
Click here to see answer by checkley77(12569)

Question 272054: (2,4),(x,8)m=-2
how do you find x or y?
Click here to see answer by checkley77(12569)

Question 272110: the perimeter of a rectangle is 114 feet. it's length is three more than twice its width. find the dimensions of the rectangle
please show the work
Click here to see answer by rfer(12678)

Question 272069: 50% of what number is 45
Click here to see answer by rfer(12678)

Question 272183: Adult ticket $5 student ticket $3 Ben collected $180 for the 50 tickets he sold. How many adult and student tickets ded he sell? show all work?
Click here to see answer by stanbon(57424)

Question 272201: If you double Lisa's age and then subtract 6, you get Paul's age. 2 years ago, the sum of their ages was 29. How old is each person?
Click here to see answer by mananth(12270)

Question 272379: Solve using any method! y=-0.7x+6.9
y=1.2x-6.4
Click here to see answer by checkley77(12569)

Question 272377: Solving using the substitution method:
8x - 5y = -47
4x + 3y = -7
I got some help from the site, but I dont know how it derived to that answer. When doing it long hand, I couldn't get the same results.
Expressing x as a function of y (from the first equation) x = (-47 +5y)/8
Substituting this expression into the second equation:
4(-47-5y)/8+3y = -7
Simplifying this expression:
44y = 132 or y = 3
Now, substituting y = 3 back into the x expressed as a function of y:
x = (-47+5y)/8 = -4

Click here to see answer by scott8148(6628)

Question 272564: the length of a rectangle is 5 units longer than its width. The perimeter of this rectangle is 74cm. determine the length and the width of this rectangle.
Click here to see answer by oberobic(2304)

Question 272603: x = 4y + 5
x - 3y = -2
Click here to see answer by stanbon(57424)

Question 272598: The cost to run machine 1 for an hour is $2. During that hour, Machine 1 produces 240 bolts and 100 nuts. The cost to run machine 2 for an hour is $2.40. During that hour, Machine 2 produces 160 bolts and 160 nuts. With a combined running time of no more that 30 hours, how long should each machine run to produce an order of at least 2080 bolts and 1520 nuts at the minimum operating cost?
I can't figure out the proper equations to graph.
Click here to see answer by stanbon(57424)

Question 272602: x = 4y
2x + 3y = 44

Click here to see answer by unlockmath(1606)

Question 272861: how do you solve
10x+2y+1z=885
5x+4y+1z=865
9x+6y+6z=1410
Click here to see answer by jim_thompson5910(28598)

Question 272859: how do you solve
2x=3y-z=17
y=-3z-7
2x=z+2
Click here to see answer by checkley77(12569)

Question 272858: how do you solve
x+y+z=-54
x=-6y
z=14y
Click here to see answer by checkley77(12569)

Question 272796: Create a system of linear equations from the following information. I jog four times a week, and do static runs (intervals) three times a week. The number of miles I run depends on the number of static runs I complete. For instance, I run 2 miles each time I jog and then on my interval days, I run an additional half mile after each static workout, (I normally complete four static workouts each interval day).
...
So I guess the miles I run, (M) = 2 + .5X the number of static runs I complete (s). So it would be written as M = 2 + .5s Where M = the miles I run and s = static workouts. How many miles do I run each week? Create a system of linear equations.
Click here to see answer by richwmiller(9143)

Question 272976: x + y = -2
2x - y = 5
Click here to see answer by stanbon(57424)

Question 273079: I'm having trouble. I solved for y not x. It was:
2x+y=5
1x-2y=4
I ended up doing this:
2x+y=5
-2x -2x
________
y=5-2x
etc. what did i do wrong?
Click here to see answer by edjones(7569)

Question 273323: 2/3x-1/6=x/9
Click here to see answer by stanbon(57424)

Question 273664: Solve the system of equations and enter the solution as an ordered pair.
4x - 7y = -23
8x + 5y = 49
Click here to see answer by richwmiller(9143)

Question 273702: 3x-2y=2
5x-5y=10
x=?
y=?
Not sure where to start at.
Click here to see answer by solver91311(16897)

Question 273711: Solve the system of equation by graphing. Im lost.
x+y=7
x-y=-5
Click here to see answer by solver91311(16897)

Question 273560: Safety rent a truck rents a truck at a daily rate of 41.95 plus 29 cents per mile city rentals rents the same size truck for 38.95 plus 31 cents per mile for what mileage is the cost the same
Click here to see answer by ankor@dixie-net.com(15667)

Question 273818: Solve a system of four linear equations and four variable:
2x+4y+2z+3w=-7
-3x-2y+5z+4w=11
4x-3y-2z-3w=11
-2x+3y-5z-4w=-16
Click here to see answer by Alan3354(30993)

Question 273972: find the slope if it exist
x=-5
Click here to see answer by Tobiasz(54)

Question 273972: find the slope if it exist
x=-5
Click here to see answer by richwmiller(9143)

Question 273918: The sum of the page numbers on two facing pages is 245. The product of the numbers is 15006. What are the page numbers?
Click here to see answer by Alan3354(30993)

Question 274231: Solve the system of linear equations.If the system has infinite number of solutions,give three solutions.
3x-y=2x-7
2x+5=2y-9
Thank you so much for your help!
I can't find 3 solutions.
Click here to see answer by checkley77(12569)

Question 274439: Here is my problem.
The perimeter of the rectangle is 24 and the perimeter of the triangle is 23
Here are the sides of the rectangle:
side 1- x
side 2- 3y
side 3- x
side 4- 3y

here are the sides of the isosoles triangle:
side 1- x+1
side 2- x+y
side 3- y+6
Write a system of linear equations to represent this problem.
How would I do that?
Click here to see answer by stanbon(57424)

Question 274486: perimeter of a triangle
The perimeter of the triangle shows the accompanying figure 12 meters
Determine the value of x, x+1, x+2 by solving the equation
x+(x+1)+(x+2)=12
Click here to see answer by anantha(86)

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