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Question 141088: 3x+4y=17
6y-2x=-20
Im stuck.
Click here to see answer by rapaljer(4667)

Question 141089: How do I solve by using a system of two equations in two variables?
A duck can fly 2400 m in 10 min with the wind. Against the wind, it can fly only two thirds of this distance in 10 min. How fast could the duck fly in still air? What is the rate of the wind?
Click here to see answer by stanbon(57361)

Question 141076: How do I solve using a system of two equations in two variables?
When Lucy swims with the current, she swims 18km in 2 hours. Against the current, she can swim only 14km in the same time. How fast can Lucy swim in still water? What is the rate of the current?
Click here to see answer by stanbon(57361)

Question 141110: Okay, my last problem and I just can't find a whole answer. How do I solve using a system of two equations in two variations?
A salmon swims 100 m in 8 min downstream. Upstream, it would take the fish 20 min to swim the same distance. What is the rate of the salmon in still water? What is the rate of the current?
Click here to see answer by scott8148(6628)

Question 141227: What are the x- and y-intercepts of the line with equation 4x + 5y = 40?
Click here to see answer by checkley77(12569)

Question 141236: Well i have to solve the following system of equations by substitution
0.5x-2y=1
-3y+x=4
I understand that I must get of the the equations to equal to either x or y so i can substitute.
i'll try the second one
-3y+x=4
x=4-3y is that right? if so, what to do next?
Click here to see answer by stanbon(57361)

Question 141225: how do you solve 1/3p=2/5p+2/3
Click here to see answer by stanbon(57361)

Question 141263: How do I solve uing two equations in two variable?
A shipment of TV sets, some weighing 30kg each and the others weighing 50 kg each, has a total weight of 880 kg. If there are 20 sets all together, how many weigh 50 kg?
I got the first equation of: 880=30t+50k, but can't figure out the second equation.
Click here to see answer by scott8148(6628)

Question 141292: How do I solve using a system of two equations in two variables?
Four years ago, Katie was twice as old as Anne was then. In 6 years, Anne will be the same age as Katie is now. How old is each now?
Click here to see answer by stanbon(57361)

Question 141295: How do i solve using a system of two equations in two variables?
Adam is 5 years younger than Eve. In one year, Eve will be 3 times as old as Adam was 4 years ago. Find their ages now?
Click here to see answer by Edwin McCravy(8909)

Question 141274: I want to thank everyone that has helped me with the last few weeks of algbra that i still do not understand totally, but at least I am trying....
Solve by the elimination method.
3x + 4y = 4
6x + 8y = 8
help please.
Click here to see answer by edjones(7569)

Question 141280: How do I solve using a system of equations in two variables?
Three times the larger of two numbers is equal to four times the smaller. The sum of the numbers i 21. Find the numbers.
Click here to see answer by oscargut(891)

Question 141294: How do I solve using a system of two equations in two variables?
Jack is twice as old as Jill. In two years, Jack will be 4 times as old as Jill was 9 years ago. How old are they now?
Click here to see answer by scott8148(6628)

Question 141290: How do I solve by using a system of two equations in two variables?
Five years ago, Tom was one third as old as his father was then. In 5 years, Tom will be half as old as his father will be then. Find their ages now.
Click here to see answer by scott8148(6628)

Question 141359: How do I solve using a system of two linear equations in two variables?
Barry is 8 years older than his sister. In 3 years, he will be twice as old as she will be then. How old is each now?
Click here to see answer by nabla(475)

Question 141360:
How do I solve by using a system of two equations in two variables?
Jennifer is 6 years older than Sue. In 4 years, she will be twice as old as Sue was 5 years ago. Find their ages now.
Click here to see answer by checkley77(12569)

Question 141363: How do I solve by using a system of two equations in two variables?
The units digit of a two-digit number is 1 less than 3 times the tens digit. If the digits are reversed, the new number is 45 more than the original number. Find the number.
Click here to see answer by ankor@dixie-net.com(15656)

Question 141361: How do I solve using a system of two equations in two variables?
The sum of the digits of a two-digit number is 9. The value of the number is 12 times the tens digit. Find the number.
I think the first equation is x+y=9
Click here to see answer by checkley77(12569)

Question 141416: How do i solve using two equation with two variables?
Jennifer is 6 years older than Sue. In 4 years, she will be twice as old as Sue was 5 years ago. Find their ages now.
My teacher said the answers are not 8 & 14.
Click here to see answer by scott8148(6628)

Question 141389: y=x^2+2x-1
y=3x+5
Click here to see answer by checkley77(12569)

Question 141370: How do I solve by using two equations and two variables?
The sum of the digits of a two-digit number is 12. If 15 is added to the number, the result is 6 times the units digit. Find the number.
Click here to see answer by ankor@dixie-net.com(15656)

Question 141480: A motorboat can go 8 miles downstream on a river in 10 minutes. It takes 30 minutes for this boat to go back upstream the same 8 miles. Find the speed of the boat in still water.
Click here to see answer by scott8148(6628)

Question 141500: I am so stuck! How do I solve using two equations with two variables?
The tens digit of a two-digit number is twice the units digit. If the digits are reversed, the new number is 36 less than the original number. Find the number.
Click here to see answer by solver91311(16897)

Question 141498: How do I solve using two equations with two variables?
The units digit of a two-digit number is 4 times the tens digit. If the digits are reversed, the new number is 54 more than the original number. Find the number.
Click here to see answer by checkley77(12569)

Question 141511: 5y = -7 - 2x
2x - 3y = 33
Click here to see answer by checkley77(12569)

Question 141497: How do I solve using two equations with two variables?
The sum of the digits of a two-digit number is 11. If 27 is added to the number, the digits will be reversed. Find the number.
Click here to see answer by ankor@dixie-net.com(15656)

Question 141534: 4x + 3y = 2
Click here to see answer by solver91311(16897)

Question 141534: 4x + 3y = 2
Click here to see answer by jim_thompson5910(28595)

Question 142227: Another quiz question:
Find an equation of the line containing (-4, -3) and perpendicular to the line 2x-7y=14.
Click here to see answer by scott8148(6628)

Question 142457: .5x + 2y = 9
4x - 15y = 2
Click here to see answer by checkley77(12569)

Question 142693: Hello, I've got to solve this word problem using a system of linear equations and I do not know where to begin, it seems to me like all the variables are just not there. Any help would be appreciated. Thank you in advance.
A bricklayer and an electrician together spend 90 hours working on a new house. If the bricklayer earns $12 per hour, the electrician earns $16 an hour, and the owner pays them a total of $1350 for their work, how many hours does each worker spend on the house?
Click here to see answer by stanbon(57361)

Question 142702: Could someone please help me with this word problem, this problem needs to be solved by using systems of linear equations. Thank you in advance for your help.
In a triangle, the sum of the interior angles is 180 degrees. If angle A is three times as large as angle B, and angles B and C sum to 90 degrees, what is the measure of each angle?
Click here to see answer by stanbon(57361)

Question 142764: I know how to solve a linear equation with three variables by using two of the three equations to eliminate one variable and then use a different pair of equations to eliminate the same variable and then you can solve those equations. I am doing some word problems and writing the first two equations with three unknown variables is easy but I cannot seem to write the third.
Mike has 19 coins (nickels, dimes and quarters) in his piggy bank with a total value of $2.35. There are 2 more dimes than nickels. How many of each type does Mike have?
N+D+Q=19
5N+10D+25Q=235
?

With the first two I can multiply the first by –5 to eliminate N. I need another equation. Help?
----------------
Fred, Tiger and Nancy play a round of golf together. Their combined score is 223. Fred’s score was 3 more than Nancy’s and Tiger’s score was 7 more than Fred’s. What was each person’s score.
You would think something simple like
F=N+3
T=F+7
223=T+F+N
But I need three equations with three unknown variables.
Click here to see answer by stanbon(57361)

Question 142763: I need to solve the system of linear equations
x/4 - y/11 = -9/44
x/6 - y/13 = -1/26
Click here to see answer by stanbon(57361)

Question 142827: find an equation of the line containing (-1,6) and (0,-3) and write the result in slope intercept form
Click here to see answer by jim_thompson5910(28595)

Question 142830: how do you solve x-8y=37 3x+8y=-17 by using the elimanation method it doesnt really help with the steps can you or anybody show me.
Click here to see answer by nabla(475)

Question 142918: I need help with this word problem which needs to be solved using a system of two linear equations. Thank you in advance for your help.
A university bookstore recently sold a wirebound graph-paper notebook for $2.50, and a college-ruled notebook for $2.30. At the start of spring semester, a combination of 50 of these notebooks were sold for a total of $118.60. How many of each type were sold?
Click here to see answer by jojo14344(1512)

Question 142969: Any help with this system of linear equation would be appreciated.
In a triangle, the sum of the interior angles is 180 degrees. If angle A is three times as large as angle B, and angles B and C sum to 90 degrees, what is the measure of each angle?
Click here to see answer by Earlsdon(6287)

Question 142968: Any help with this system of linear equations will be appreciated.
A bricklayer and an electrician together spend 90 hours working on a new house. If the bricklayer earns $12 per hour, the electrician earns $16 an hour, and the owner pays them a total of $1350 for their work, how many hours does each worker spend on the house?
Click here to see answer by Earlsdon(6287)

Question 142967: Could any one help me with this system of linear equation as a word problem. Thank you in advance for your help.
A shopper buys three oranges and five lemons for $10.26, while a second shopper buys four lemons and six oranges for $11.16. What is the price of each fruit?
Click here to see answer by Earlsdon(6287)

Question 143008: I need help finding the solution to this system of linear equation. Any help would be appreciated. Thank you in advance.
y = 2x + 3 and y = -x – 4
Click here to see answer by vleith(2825)

Question 143050: I need the formula to express how much money I would have after 20 years if I start with one dollar and the money doubles every year. My assignment is to put the formula on a spread sheet and generate a graph. I can do that, I just don't know how to come up with the formula.(I've been out of high school for 38 years)
Click here to see answer by scott8148(6628)

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