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

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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 stanbon(57967)

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(28715)

Question 166684: x=7/2y+4
2x-7y=8
solve by any method
Click here to see answer by jim_thompson5910(28715)

Question 166957: tell weather each function is a linear if so graph it
5+3y=8
Click here to see answer by checkley77(12569)

Question 166956: tell weather each equation is linear,write it in standard form
2x=y/3-4
Click here to see answer by checkley77(12569)

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(31530)

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(31530)

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(1512)

Question 167443: Please answer this question 3R/5-4=11
Click here to see answer by jojo14344(1512)

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(28715)

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(57967)

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)

Question 167729: I dont know where to start.
Please help me in solving this question
Simultaneous equation
3x-4y=5
3x^2-xy-3y^2=21

Click here to see answer by Alan3354(31530)

Question 167828: Solve each system by the substitution method.
x – y = 5
2x = 2y + 14

3x + y = 2
-x – 3y = 6

3x – 4y = 9
-3x + 4y = 12
Click here to see answer by midwood_trail(310)

Question 167863: The problem is dealing with systems of linear equations in more than two variables. I have to solve each system of equations. I have tried but can't seem to get the answer using the substitution or elimination method.
3x + 4y - z = -7
x - 5y + 2z = 19
5x + y - 2z = 5
Click here to see answer by ankor@dixie-net.com(15746)

Question 167867: I have to solve each system of equations by the elimination method.
3/4x + 1/3y = 1
1/2x + 2/3y = 0
Click here to see answer by checkley77(12569)

Question 168245: how to eliminate x and y regarding with this problem?
3x+2y = 8
3x+2y = 2
Click here to see answer by edjones(7569)

Question 168298: Elementary and Intermediate Algebra, 3e ISBN: 9780073533490
Page 487 Number 1
Solve the system by graphing.
1.
x + y = 4
y = 2x + 1
Click here to see answer by stanbon(57967)

Question 168299: Elementary and Intermediate Algebra, ISBN: 9780073533490

Solve each system by substitution.
page 487 number 3
y=x-5
3x-4(y-2)=28-x
Click here to see answer by stanbon(57967)

Question 168320: The distance that a free falling body falls varies directly with the square of the time it falls. If a body fall 400 feet in 5 seconds, how far does it fall in 3 seconds?
Click here to see answer by Mathtut(3670)

Question 168319: The area of a kite varies jointly with the lengths of its two diagonals. If a kite with the area 30 inches squared has one diagonal of length 10 inches and the other diagonal of length 6 inches, what is the area of a kite with diagonals of length 8 inches and 13 inches?
Click here to see answer by Mathtut(3670)

Question 168297: Elementary and Intermediate Algebra, 3e ISBN: 9780073533490
Page 487 Number 14
For each problem, write a system of equations in two or
three variables. Use the method of your choice to solve each
system.
14. One night the manager of the Sea Breeze Motel rented
5 singles and 12 doubles for a total of $390. The next night
he rented 9 singles and 10 doubles for a total of $412.
What is the rental charge for each type of room?
Click here to see answer by Mathtut(3670)

Question 168603: how do you solve this
5(x-3)+4x-1=x+3(x-3)
Click here to see answer by checkley77(12569)

Question 168732: solve each system by any method
1 x-3y=1
3x-5y=-5
2 2x-3y=5
4x-6y=3
Click here to see answer by jim_thompson5910(28715)

Question 168735: solve using any methord
x/3-y/2=3
x/2+y/3=7/3
Click here to see answer by jim_thompson5910(28715)

Question 168738: 1.
3x=-5-x
2x+y=-5
2.
3x-5y=7
2x-y=-7
3.
x-3y=1
3x-5y=-5
Click here to see answer by jim_thompson5910(28715)

Question 168423: x-y+4=0
Click here to see answer by jojo14344(1512)

Question 168849: Please help me solve this equation:
using a system of two equations.

The sum of a certain number and a second number is -42. The first number minus the second is 52. Find the numbers.
Click here to see answer by Mathtut(3670)

Question 168889: Using Substitution
4x + 2y = 1
2x + 3y = .70
Solving for X in the first problem
4x + 2y - 2y = 1 - 2y
4x = 1-2y
4x/4 = (1-2y)/4
x = (1 - 2y)/4
Substitute x into first equation (this is where I get lost)
2(1-2y/4) + 3y = .70
the example on this website says it should be 2(1+2y)/4+3y=.70, but if x = (1-2y)/4, how can you just change it to the 1+2y? Then also how do I solve the problem? If you could give me step by step with explanations so I understand that would be very helpful. This is my calculations:
2-4y/4 + 3y = .70 (multiplied 2 by everything in parentheses)
2-y+3y=.70 (4's cancel eachother out)
2+2y=.70 (3y minus 1y = 2y)
2+2y/2 = .70/2 (divide both sides by 2)
1+y = .35
y = .35 - 1 (subtract 1 from each side)
y = -.65

Click here to see answer by Fombitz(13828)

Question 168823: y-11=3x-6

Click here to see answer by checkley77(12569)

Question 169044: find the equation of the line with slope 8 and passing through(-5,-6).....
Click here to see answer by Alan3354(31530)

Question 169187: Hello, I just need help with how to solve this equation:
y-1/5x=-2
I know how to solve the problems, but only if there in simplified form already.. You don't have to give me the answer but just tell me how to simplfy it.
Thank you!!
Click here to see answer by Alan3354(31530)

Question 169309: Find all numbers for which the rational expression is not defined.
6/b+6
Click here to see answer by Fombitz(13828)

Question 169438: in 1995 perry hall middle school had 98 girls in gt math. in the year of 1998 it had 294 girls. write an equation.

thank you
Click here to see answer by jojo14344(1512)

Question 169624: Solve each system by substitution. Determine whether the equations are independent, dependent or inconsistent:
2x-y=4
2x-y=3
Click here to see answer by jim_thompson5910(28715)

Question 169662: having trouble solvin this probolem using addition method,substitution and graphing not sure ifm i am suppose to have the same answer for all three methods
3x+2y=22
5x-4y=0
Click here to see answer by stanbon(57967)

Question 169652: NEED HELP PLEASE!!!!
solve by graphing
x-2y=-8
3x+4y=6
Click here to see answer by jim_thompson5910(28715)

Question 169669: I am a math tutor on this site, can someone please help with a method of systems of equations?
I need to know the name of this method of solving
Ex.
.

.

.
First solve for a variable, we will solve for "x" in each equation
.
First equation,
.
, move "4y" to the right side
.
= = or
.
is our first answer, keeping that answer in mind we solve for "x" in the other equation
.
Second equation,
.
, move (-y) to the right side
.
= = or , now divide each side by "2"
.
= =
.
Second answer is , then I would say, since these two answers equal "x" both answers will equal each other, then I would put them in an equation
.
, then I would solve for "y"
.
, then I would show the student the cross multiplication
.
We come up with , then just solve, in which we would get
.
Then I would replace "y", and go through the math, and find that
.
What would you call this method ( when you solve for a variable in both equations, and put your answers together in an equation and solve )
.
Solution set = (20,0)
.
Please don't answer if you don't know the name of this method
.
Thanks ahead of time, Electrified_Levi

Click here to see answer by stanbon(57967)

Question 169738: I have no idea where to start on this problem. PLease help.
7x/8-4=x
Click here to see answer by midwood_trail(310)

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