Questions on Algebra: Systems of Linear Equations answered by real tutors!

Tutors Answer Your Questions about Linear-systems (FREE)

Question 709256: how do I solve x + 7y = 39 and 3x - 2y = 2 by using substitution?

Click here to see answer by checkley79(3341)

Question 709245: Suppose that the length of a rectangle is 3 in longer than the width and the perimeter ofathe rectangle is 78.
a. Set up an equatio involving only w, the width of the rectangle
b. Solve linear equation algebraically to find the width of the rectangle. Find the length as well.
c. Using the the same length you have as you answer and part b find a new perimeter if the new width is 4 more than one third of the length.
Click here to see answer by josgarithmetic(39617)

Question 709251: PLEASE HELP!!!!!!!!!!!!!!!!!!!
SOLVE FOR X
2x + y + z = 0
3x - y + z = 3
7x - 5y - 3z = 15
thanks.
Click here to see answer by KMST(5328)

Question 709251: PLEASE HELP!!!!!!!!!!!!!!!!!!!
SOLVE FOR X
2x + y + z = 0
3x - y + z = 3
7x - 5y - 3z = 15
thanks.
Click here to see answer by hheuler(6)

Question 709375: how do I solve by elimination?
-0.3x-0.1y=-0.2
2/7x-3/14y=5/14
Click here to see answer by jsmallt9(3758)

Question 709325: does anyone know how to solve x,y,z equations for x and explain?!

2x + y + z = 0
3x - y + z = 3
7x - 5y - 3z = 15
thanks!
Click here to see answer by jsmallt9(3758)

Question 709430: Determine whether each system of linear equation has one and only one sol. Infinite many or no sol.
3/2x-2y=4 and x+1/3y=2 couldu help me with this problem I am lost
Click here to see answer by KMST(5328)

Question 709505: *Solving systems of Linear Equations in Three Variables by Elimination*
does anyone know how to solve x,y,z equations for x and explain?!
2x + y + z = 0
3x - y + z = 3
7x - 5y - 3z = 15
thanks!
Click here to see answer by stanbon(75887)

Question 709895: Please help me solve this equation: -16x+2y=-2, y=8x-1

Click here to see answer by MathLover1(20850)

Question 710007: I was wondering how the below equations have an infinite number of solution.
2x+3y=6
4x+6y=12
I tried multiplying one of the equation to a negative number so I can cancel either the x or y (elimination), but the final result will make me cancel out both the x and y and that doesn't make sense to me.
I also tried the substitution, but I can't seem to do it right.

Click here to see answer by josgarithmetic(39617)

Question 710236: The number of internet users I in millions during year X, where X is greater than or equal to 2000 can be approximated by the following formula
I =112x-223,515
Approximate the year there were 950 million users for the first time.
Round to the nearest year as needed
Click here to see answer by stanbon(75887)

Question 710309: -12X+ y=43
7x-10y=22
there is a space before the y and i cannot figure out the equation i keep getting -4,-5
Click here to see answer by solver91311(24713)

Question 710410: Substitition Method, Please help me the solutions
3x+4y=4
2x y=6
-y-(6+2x)
3x+4(6-2x)=4
3x+24-8x=4
5x=20/5=(4,2)

Click here to see answer by Alan3354(69443)

Question 710587: Find three consecutive integers such that twice the second subtracted from the sum of the other three integers is sixteen.

Click here to see answer by nerdybill(7384)

Question 710600: Serving Size and Price
6 nuggets= $2.40
10 nuggets= $3.60
15 nuggets= $5.10
24 nuggets= $7.80
Draw a graph of this information and answer the following questions:
a. What is the equation of this graph?
b. What is the slope of this graph?
c. What is the real-world significance for the slope?
d. What is the y-interecept of this graph?
e. What is the real-world significance for the y-intercept?
Click here to see answer by lynnlo(4176)

Question 710622: x+y=1
2x+y=0

Click here to see answer by lynnlo(4176)

Question 710846: x = -4y
3x + 2y = 20
Click here to see answer by jim_thompson5910(35256)

Question 710791: I need help with this open ended system of linear inequality!
You are buying movie passes and gift certificates as prizes for an event. You need at least 5 movie passes and 2 gift certificated. A movie pass costs $6.00 and a gift certificate costs $10.00. The most you can spend is $70.00. write a system of linear inequalities that shows the number of movie passes (x) and gift certificates (y) that can be purchased. Graph the system. Use the graph to determine if you can buy 6 movie passes and 3 gift certificates. Please explain your answer.
Click here to see answer by josgarithmetic(39617)

Question 710856: y = x - 1
x + y = 3

Click here to see answer by Alan3354(69443)

Question 710854: y = x - 1
x + 1 = 3

Click here to see answer by Alan3354(69443)

Question 711195: I need help with this homework..i just need a step by step so i can go on with the rest of the problems..for example i have this:1/2 x 7 = 3 y/2 its one and a half as in a fraction times seven equals three and y and half..
Click here to see answer by tutor_paul(519)

Question 711228: i have homework that i do not understand and have no examples for if you could help me with an example i would appreciate it..i have 1/2 x 7 as a whole number = 3 as a whole number y/2 as in a fraction i have to figure out the y..1/2 x 7 =3 y/2..another one is 6/7 x 2/3 =4/y...
Click here to see answer by tutor_paul(519)

Question 711436: Hi, I am confused about this problem and was wondering if you could help me.
Solve the system of equations by substitution:
x + 3y = 1
-3x - 3y = -1
I already tried to solve this and ended up with x=0 and I was not able to go from there. It would be great if you could help me. Thank you
Click here to see answer by josgarithmetic(39617)

Question 711465: 20/x=5
Click here to see answer by rfer(16322)

Question 711673: a+9b=23
a+2b=2
Use the elimination method to solve the systems of equations
Click here to see answer by lynnlo(4176)

Question 711673: a+9b=23
a+2b=2
Use the elimination method to solve the systems of equations
Click here to see answer by Alan3354(69443)

Question 711679: I was wondering how would you solve a linear system using subsitution? My teacher taught the class this in like 10 min and I'm not sure.. Can you show me to steps to answer -x+2y=-6 and 8x+y=31 thanks!
Click here to see answer by stanbon(75887)

Question 711774: Solve: 4/7x-3/2=x-1/7
Click here to see answer by stanbon(75887)

Question 711785: I have 5806 fans today which is is 162% increase from last year. How many fans did I have last year.
Click here to see answer by lynnlo(4176)

Question 711811: A landscaping company needs 200 gallons of 24% fertilizer to fertilize the shrubs in an office park. They have in stock 30% fertilizer and 20% fertilizer. How much of each type should they mix together?
Click here to see answer by lwsshak3(11628)

Question 712019: I need help setting up the second part of the equation.
Zelma is eighteen years older than her son. She was three times as old as he was one year ago. How old are they now?
I have z=18+s
Thanks:)
Click here to see answer by Menjax(62)

Question 712099: How do you graph linear equations? I don't understand and i need a easier way to do it.
Click here to see answer by tutor_paul(519)

Question 712161:
Click here to see answer by jim_thompson5910(35256)

Question 712410: Ms anna receives a bill of N$45860 for 244 units of electricity and 315 units of water. last month, he was billed N$43922 for 310 units of electricity and 201 of water. it the unit price for these commodities did not change, how much would he play for 312 units of electricity and 294 unit of water?
Click here to see answer by stanbon(75887)

Question 712471: 2p/(p^2-1) = 2/(p+1) -1/(p-1)
Click here to see answer by lynnlo(4176)

Question 712474: 8x+3/(x) = 3x
Click here to see answer by lynnlo(4176)

Question 712475: 1/(x+4) + x/(x-4) = -8/(x^2-16)
Click here to see answer by lynnlo(4176)

Question 712469: 2/(x-1) -2/3 = -1/(x+1)
Click here to see answer by lynnlo(4176)

Question 712482: 3x/ (x^2+5x+6) = 5x/ (x^2+2x-3) - 2/(x^2+x-2)
Click here to see answer by lynnlo(4176)

Question 712485: x+4/ (x^2-3x+2) - 5/(x^2-4x+3) = x-4/ (x^2-5x+6)
Click here to see answer by lynnlo(4176)

Question 712485: x+4/ (x^2-3x+2) - 5/(x^2-4x+3) = x-4/ (x^2-5x+6)
Click here to see answer by MathTherapy(10552)

Question 712461: 4x-2y-3z=8
Click here to see answer by lynnlo(4176)

Question 712628: When I graph y is greater than or equal to x+4 and y is less than 2x-1, there is no overlapping, so I believe I am doing it wrong.
Click here to see answer by Menjax(62)

Question 712835: first clear of fractions then solve using substitution
x/2 - y/3= 5/6
x/5 - y/4= 29/10
Click here to see answer by Alan3354(69443)

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