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Question 165294: Solve the system of equations using the substitution method.
If the answer is a unique solution, present it as an ordered pair: (x, y). If not, specify whether the answer is �no solution� or �infinitely many solutions.�
3x + y = 7
4x � y = 21

Click here to see answer by jim_thompson5910(35256)

Question 165293: Solve by the substition method
8m+n=7
m-6n=56
Click here to see answer by jim_thompson5910(35256)

Question 165385: How do you use substitution to solve each system of equations.
{12x+y=21
{18x-3y=-36
Click here to see answer by jim_thompson5910(35256)

Question 165447: I have to solve the system of equations which are
2x-4y+2z=16
-2x+5y+2z=-34
x-2y+2z=4
I have simplified the 3rd equation to x=2y-2z+4. i then put that into the first equation and had 2(2y-2z=4)-4y+2z=16 to get z equals -4. my problem is finding the x and y variables. when i try to find them my y's and x's always cancel each other out. please help me. :)
Click here to see answer by scott8148(6628)

Question 165451: Adult tickets for a play cost $9 and child tickets cost $3. If there were 24 people at a performance and the theater collected $186 from ticket sales, how many children attended?
Click here to see answer by stanbon(75887)

Question 165449: Solve the system by graphing.
x + y = 3
x + y = -1
Click here to see answer by jim_thompson5910(35256)

Question 165439: Solve the system by addition or substitution.
-9x - 3y = 22
y = -3x - 6
Click here to see answer by jim_thompson5910(35256)

Question 165490: 2y - x =3
x = 3y � 5
Solve by substitution method.
Click here to see answer by KnightOwlTutor(293)

Question 165485: y=4x-8
y=2x+10
Click here to see answer by KnightOwlTutor(293)

Question 164189: solve the system:
5x-3y+z=-7
4x+5y+3z=-2
2x-3y+5z=22
show work and i think you can solve it in the calculator by matrices right?
if you know both ways please show thanks!

Click here to see answer by Alan3354(69443)

Question 165569: A small company produces both bouquets and wreaths of dried flowers. the bouquets take 1 hour of labor to produce, and the wreaths take 2 hours. The labor available is limited to 80 hours per week, and the total production capacity is 60 items per week. Write a system of inequalities representing this situation, where x is the number of bouquets and y is the number of wreaths.
Click here to see answer by ankor@dixie-net.com(22740)

Question 165544: A boy rows his boat 8 km downstream in 1 hr and 4 mins and return in 2 and 2/7hr.At what rate he will row in still water.What is the rate of the current.
Click here to see answer by checkley77(12844)

Question 165784: 4x^2>13x-3
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Question 165843: alice invested a portion of $32,000 at 9% interest and the balance at 11% interest. How much did she invest at each rate if her total income from both investments wa $3200.
Click here to see answer by checkley77(12844)

Question 165920: The probability that San Francisco plays in the next super Bowl is 9 times the probability that they do not play in the Super Bowl. The probability that San Francisco plays in the next super Bowl plus the probability that the don't play in the Super Bowl is 1. What is the probability that San Francisco plays in the next Super Bowl?

I thought you would use the equation: Ax + By = C (9x + By = 1)
9x = 1 - By
9x/9 = 1/9 - By/9
x = -By/9 ?
Not really sure where to begin.

Click here to see answer by edjones(8007)

Question 166089: find the solution to the following system of linear equations by
a) graphing
b) substitution
c) addition / subtraction method
4x - 3y = 2
-2x + 3y = -4
Click here to see answer by jim_thompson5910(35256)

Question 166125: I am needing to solve this equation by the addition (elimination method)
2x+4y=8
7x+2y=10
Can you help me?
Click here to see answer by jim_thompson5910(35256)

Question 166181: 2x+y=7
y=mx+b
Click here to see answer by elima(1433)

Question 166281: -x-5y=-1
2x+3y=-5
Click here to see answer by jim_thompson5910(35256)

Question 166266: Solve the following equation for x: 3(x + 2) = 7x – 10
Can someone please help me with this equation. Thank you
Click here to see answer by checkley77(12844)

Question 166266: Solve the following equation for x: 3(x + 2) = 7x – 10
Can someone please help me with this equation. Thank you
Click here to see answer by scott8148(6628)

Question 166294: Find the equation of the line that is parallel to y = 6x � 15 and passes through the origin.
Can someone please help? Thank you
Click here to see answer by Mathtut(3670)

Question 166292: find the present value of an investment at 4% annual simple interest and is worth $6900 after 7 years?

Click here to see answer by Fombitz(32388)

Question 166322: Find the equation of the line (in y = mx + b form) that passes through the points
(-8, 6.5) and (9, -11)
Csn someone please help. I am having trouble with the decimal. Thank you
Click here to see answer by Fombitz(32388)

Question 166357: solve by substituion
2x-3y+6z=-21
-5x+4y+z=3
7x-7y-4z=-6
Click here to see answer by jim_thompson5910(35256)

Question 166600: If you earned an average of $25,000 over your working life and you retire after 2005 at the age of 62,63,64, then your annual social security benefit will be $7,000, $7,500 or $8,000, respectively(ssa.gov). There is a linear equation that gives the annual benefit B in terms of the age A for these three years. Find the Equation
Click here to see answer by gonzo(654)

Question 166603: A credit manager rates each applicant for a car loan on a scale of 1 through 5 and then determines the interest rate from the accompanying table FIND THE EQUATION of the linear in slope-intercept form that goes through these points: (1,24)(2,20)(3,16)(4,12)(5,8)
Click here to see answer by nerdybill(7384)

Question 166627: I don't understand this method of solving? could you show me both parts of this problem in the long form for my reference.
Solving:
4x+9y = 395
1x+y = 80

Using Substitution Method.
Expressing x as a function of y (from the first equation) x = (395 -9y)/4
Substituting this expression into the second equation:
1(395+9y)/4+y = 80
Simplifying this expression:
(-5)y = -75

Click here to see answer by jim_thompson5910(35256)

Question 166684: x=7/2y+4
2x-7y=8
solve by any method
Click here to see answer by jim_thompson5910(35256)

Question 166957: tell weather each function is a linear if so graph it
5+3y=8
Click here to see answer by checkley77(12844)

Question 166956: tell weather each equation is linear,write it in standard form
2x=y/3-4
Click here to see answer by checkley77(12844)

Question 167243: flying against the jetstream, a jet travels 5250km in 7hours. Flying with the jetstream the same jet travels 6900km in 6hrs. what is the speed of the jet in still air, and what is the speed of the jetstream?
Click here to see answer by Alan3354(69443)

Question 164629: Write slope-intercept form of the equation for the line passing through the given pair of points (-2,-6) and (9,2)
Click here to see answer by Alan3354(69443)

Question 167238: Flying against the jetstream, a jet travels 5250km in 7 hours. Flying with the jetstream, the same jet travels 6900km in 6 hours. What is the speed of the jet in still air, ans what is the speed of the jetstream?
Click here to see answer by Mathtut(3670)

Question 167338: 5x/4+1/2=x-1/2
Click here to see answer by aswathytony(47)

Question 167336: 5x/4+1/2-x-1/2
Click here to see answer by midwood_trail(310)

Question 167444: Please answer this question 3R/5-4=11 with all working thanks
Click here to see answer by jojo14344(1513)

Question 167443: Please answer this question 3R/5-4=11
Click here to see answer by jojo14344(1513)

Question 167608: 7x+3y=4, 5x+9y=10
Click here to see answer by Mathtut(3670)

Question 167608: 7x+3y=4, 5x+9y=10
Click here to see answer by jim_thompson5910(35256)

Question 167658: Can you please help me with this problem...Thank you
Suppose Bob owns 2,000 shares of Company X and 10,000 shares of Company Y. The total value of Bob's holdings of these two companies is $340,000.
Suppose Frank owns 8,000 shares of Company X and 6,000 shares of Company Y. The total value of Franks holdings of these two companies is $340,000.
a. Write equations for Bob and Frank's holdings. Use the variables X and Y to represent the values of shares of Company X and Company Y.
b. Solve for the value of a share of Company X and Company Y. Show your work so you can get partial credit even if your final answer is wrong.
Click here to see answer by stanbon(75887)

Question 167664: Please help! I am so confused!
3. Solve for X, Y, and Z in the following systems of three equations:
a. X + 2Y + Z = 6
X + Y = 4
3X + Y + Z = 8
b. 10X + Y + Z = 12
8X + 2Y +Z = 11
20X - 10Y - 2Z = 8
c. 22X + 5Y + 7Z = 12
10X + 3Y + 2Z = 5
9X + 2Y + 12Z = 14
Click here to see answer by rviksub(2)

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