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Question 570841: What is the x-coordinate of this solution?
2x+3y=-27
-3x+2y=23
My Work is Shown Below:
3(2x-3y=-27)
-3+2y=23
__________
6x-9y=81
-3x+2y=23
_________
-18x-7y=104
+18 +18
-7y=122
__ ___
-7 -7
y= -17.42
________________________________________________________________________________
Is that correct?
Answer by JBarnum(1826)

(Show Source):

You can put this solution on YOUR website!
already answered this exact question
please review http://www.algebra.com/cgi-bin/jump-to-question.mpl?question=569696

Answer 367429 by JBarnum(1809) on 2012-02-08 14:29:23 (Show Source):
i have no idea what you were trying to do and no its not correct.
easiest way is to do the elimination method but you could do substitution method if you wanted to
2x%2B3y=-27

first find the lowest common variable for y spot in both equations that will be easy to eliminate we want to eliminate the y so we can solve for the x coordinate best would be

2(2x+3y=-27)
3(-3x+2y=23)
.
4x%2B6y=-54

now subtract the 2 equations
.
4x-%28-9x%29%2B6y-6y=-54-69

divide by 13
x=-123%2F13

Question 570138: x+y=9
y=2x
Found 2 solutions by sahnikdgp, Maths68:
Answer by sahnikdgp(1)   (Show Source):
You can put this solution on YOUR website!
x+y=9......1
y=2x.......2
or,y-2x=0...2
x+y=9......1
-2x+y=0.....2
or,3x=9
or, x=3
substituting x in equation (1),
x+y=9
or,3+y=9
or,y=9-3=6
answers-:x=3
y=6

Answer by Maths68(1140)   (Show Source):
You can put this solution on YOUR website!
x+y=9.........(1)
y=2x........(2)
Put value of y from (2) to (1)
x+y=9
x+2x=9
3x=9
3x/3=9/3
x=3...............(3)
Put the value of x in (2)
y=2x
y=2(3)
y=6
x,y=3,6

Check
Put the value of x and y in (1)
x+y=9.........(1)
3+6=9
9=9
Put the value of x and y in (2)
y=2x
6=2(3)
6=6

Question 569992: List all possible pairs of integers x and y such that the product of x and y equals the sum of x and y.
Answer by ankor@dixie-net.com(12684)   (Show Source):
You can put this solution on YOUR website!
List all possible pairs of integers x and y such that the product of x and y equals the sum of x and y.
:
x + y = xy
y - xy = -x
y(1-x) = -x
y =
:
x=2, y=2 are the only integers
:

Question 570017: 0.5x+y=9
1.6x+0.2y=13
Can you show me the steps to solve this using elimination?
Answer by Alan3354(21550)   (Show Source):
You can put this solution on YOUR website!
0.5x+y=9
1.6x+0.2y=13
----------
Multiply the 1st eqn by 2 and the 2nd by 10. --> no fractions
-----
1x + 2y = 18
16x + 2y = 130
---------------- Subtract
-15x = -112
x = 112/15
-----
x + 2y = 18
112/15 + 2y = 18
y = 79/15

Question 569921: total of tickets were sold for the school play. They were either adult tickets or student tickets. The number of student tickets sold was three times the number of adult tickets sold . How many adult tickets were sold?
Answer by mananth(10539)   (Show Source):
You can put this solution on YOUR website!
let the number of adult tickets sold be x
then number of student tickets sold is 3x
Total tickets sold = 3x+x=4x tickets

Question 569855: At a circus, 135 clowns are getting into cars. Blue cars hold 20 clowns and red cars only hold 15. How many of each are there?
Answer by stanbon(48510)   (Show Source):
You can put this solution on YOUR website!
At a circus, 135 clowns are getting into cars. Blue cars hold 20 clowns and red cars only hold 15. How many of each are there?
---
20b + 15r = 135
20b = 135-15r
4b = 27 - 3r
b = (27-3r)/4
---
b = (3/4)(9-r)
-----
Graph and look for whole number solutions.
-----------------------------------------------
b = 6 when r = 1
---
Answers:
6 blue cars and 1 red car
OR
3 blue cars and 5 red cars
Or
0 blue cars and 9 red cars
===================================
Cheers,
Stan H.

Question 569696: 28:39 What is the x-coordinate of this solution?
2x+3y=-27
-3x+2y=23
My Work is Shown Below:
3(2x-3y=-27)
-3+2y=23
__________
6x-9y=81
-3x+2y=23
_________
-18x-7y=104
+18 +18
-7y=122
__ ___
-7 -7
y= -17.42
________________________________________________________________________________
Is that correct?
Answer by JBarnum(1826)   (Show Source):
You can put this solution on YOUR website!
i have no idea what you were trying to do and no its not correct.
easiest way is to do the elimination method but you could do substitution method if you wanted to

first find the lowest common variable for y spot in both equations that will be easy to eliminate we want to eliminate the y so we can solve for the x coordinate best would be
2(2x+3y=-27)
3(-3x+2y=23)
.

now subtract the 2 equations
.

divide by 13

Question 569698: 28:39 What is the x-coordinate of this solution?
2x+3y=-27
-3x+2y=23
My Work is Shown Below:
3(2x-3y=-27)
-3+2y=23
__________
6x-9y=81
-3x+2y=23
_________
-18x-7y=104
+18 +18
-7y=122
__ ___
-7 -7
y= -17.42
________________________________________________________________________________
Is that correct?
Answer by Alan3354(21550)   (Show Source):
You can put this solution on YOUR website!
What is the x-coordinate of this solution?
2x+3y=-27
-3x+2y=23
My Work is Shown Below:
3(2x-3y=-27)
-3+2y=23
__________
6x-9y=81
-3x+2y=23
_________
-18x-7y=104
+18 +18
-7y=122 ********** What happened to the x? -18x + 18 <> 0
__ ___
-7 -7
y= -17.42
________________________________________________________________________________
Is that correct?
================
2x+3y=-27
-3x+2y=23
-----
6x + 9y = -81 eqn 1 times 3
-6x+ 4y = 46 eqn 2 times 2
------------- Add
13y = -35
y = -35/13

Question 569598: how many solutions does this system of equations have???
2x+3y=6
y=-2/3x-1
it woudd be amazing if you could answer soon!
Found 2 solutions by TutorDelphia, Alan3354:
Answer by TutorDelphia(189)   (Show Source):
You can put this solution on YOUR website!
This has no solutions:
y=(-2/3)x-1 is already in slope intercept form
2x+3y=6
subtract 2x from both sides
3y=-2x+6
divide all by 3
y=(-2/3)x+2
Since these have the same slope but a different intercept they are parallel lines.

Answer by Alan3354(21550)   (Show Source):
You can put this solution on YOUR website!
2x+3y=6 --> y = (-2/3)x + 2
y=-2/3x-1
----------------
The 2 lines are parallel if you graph them.
No intersection, no solution.

Question 569457: what's
4x+3y=10
y=2x
in sustitution method??
plz answer asap!!1
thnxx
Answer by josmiceli(6769)   (Show Source):
You can put this solution on YOUR website!
(1)
(2)
Substitute (2) into (1)
(1)
(1)
(1)
(1)
and, since
(2)
(2)
(2)
So, the solution is ( 1,2 )
Here's a plot of the lines

Question 569202: What are the solutions to the equation below:
|2x+3|-5=12
I have chosen x=-5 or x=7
Answer by Alan3354(21550)   (Show Source):
You can put this solution on YOUR website!
What are the solutions to the equation below:
|2x+3|-5=12
I have chosen x=-5 or x=7
--------------
Check your answers.
|2x+3|-5=12
x = -5
|-10 + 3 |- 5 =? 12
|-7| - 5 =? 12
7-5 =? 12 Nope.
===============
|2x+3|-5=12
x = 7
|14 + 3| - 5 =? 12
17 - 5 = 12 *** 7 is correct
==============
You don't choose, you figure them out.

Question 569135: Which is the solution to the system?

x+5y = -15
y = 1/5x + 1

Below is how I solved it:
x+5(1/5x+1)=-15
x+(x+5)=-15
x^2+5=-15
x^2+5-5=-15-5
x^2=-20

Is this correct ?

Answer by Alan3354(21550)   (Show Source):
You can put this solution on YOUR website!
x+5y = -15
y = 1/5x + 1

Below is how I solved it:
x+5(1/5x+1)=-15
x+(x+5)=-15
x^2+5=-15
x^2+5-5=-15-5
x^2=-20

Is this correct ?
-----------------
x+5(1/5x+1)=-15 Sub for y is good.
x+(x+5)=-15 This is correct.
x^2+5=-15 *** Don't multiply, add.
=============
2x+5 = -15
2x = -20
x = -10
=============
x^2+5-5=-15-5
x^2=-20

Question 568731: what is x and y for this problem, whats the solution
4x+5y=48
y=3x+2
Answer by 10301650(25)   (Show Source):
You can put this solution on YOUR website!
X=2
Y=8

Question 568888: 13x+7y=88
x+8y=-38
Solve this problem using the Solution method
Answer by mananth(10539)   (Show Source):
You can put this solution on YOUR website!
13x+7y = 88 .............1
x+8y=-38 .............2
Eliminate y
multiply (1)by -8
Multiply (2) by 7
-104x-56y=-704
7x+56y =-266
Add the two equations
-97x=-970
/-97
x=10
plug value of x in (1)
13 x + 7 y = 88
130 + 7 y = 88
7 y = 88 -130
7 y = -42
y = -6
(10,-6)

Question 568670: How do you tell on a coordinate graph if it is a function or not????

Answer by richard1234(4789)   (Show Source):
You can put this solution on YOUR website!
If there are two points on the graph of the function that have the same x-coordinate, but different y-coordinates, the relation cannot be a function (assuming x is the independent variable, one x cannot map to two or more y). You can check this by (mentally) drawing vertical lines on the coordinate plane. If any of the lines touches the graph at two points, the relation cannot be a function. This is usually referred to as the "vertical line test."

If the vertical line test passes (no vertical lines touch at 2+ points) then the relation is a function, even if it cannot easily be defined.

Question 568770: How do I solve:
y=x^3-2x^2+x-1
y=-x^2+3x-1
I substituted y=-x^2+3x-1 -x^2+3x-1=x^3-2x^2+x-1
0=x^3-x^2-2x
Not sure what to do next
Answer by josmiceli(6769)   (Show Source):
You can put this solution on YOUR website!

By substitution:

Add to both sides

Factor out

The solutions are:

You can verify these by plugging them
back into

Question 568737: 4x + 7y = 8.77
8x + 14y = 15.8
I ued substitution and got x=1.2175 and y=39 over 70. Obviously I did something wrong.
Answer by mananth(10539)   (Show Source):
You can put this solution on YOUR website!
4 x + 7 y = 8.77 .............1
8 x + 14 y = 15.8 .............2
Eliminate y
multiply (1)by -2
Multiply (2) by 1
-8 x -14 y = -17.54
8 x 14 y = 15.8
Add the two equations
0 x = -1.74
which is absurd
Hence there is no solution to the system.
The lines are parallel

Question 568396: What is the Solution to the system?

2x - 3y = -27
-3x + 2y = 23
[ I got -3 for my answer]
Answer by jim_thompson5910(21667)   (Show Source):
You can put this solution on YOUR website!

Start with the given system of equations:

Multiply the both sides of the first equation by 2.

Distribute and multiply.

Multiply the both sides of the second equation by 3.

Distribute and multiply.

So we have the new system of equations:

Now add the equations together. You can do this by simply adding the two left sides and the two right sides separately like this:

Group like terms.

Combine like terms.

Simplify.

Divide both sides by to isolate .

Reduce.

------------------------------------------------------------------

Now go back to the first equation.

Plug in .

Multiply.

Add to both sides.

Combine like terms on the right side.

Divide both sides by to isolate .

Reduce.

So the solutions are and .

Which form the ordered pair .

This means that the system is consistent and independent.

Notice when we graph the equations, we see that they intersect at . So this visually verifies our answer.

Graph of (red) and (green)

-------------------------------------------------------------------------------------------------
If you need more help, email me at jim_thompson5910@hotmail.com

Also, please consider visiting my website: http://www.freewebs.com/jimthompson5910/home.html and making a donation. Thank you

Jim
-------------------------------------------------------------------------------------------------

Question 567293: What is 5*1/5?
Answer by jim_thompson5910(21667)   (Show Source):
You can put this solution on YOUR website!
5*1/5 = 5/5 = 1

So 5*1/5 = 1

Question 568518: 2x+3y=4
x+y=3
Answer by themathtutor127(34)   (Show Source):
You can put this solution on YOUR website!
x = 5, y = -2

Question 568517: Please help me solve this equation:
3x-2y=5
x=y+10
Answer by jim_thompson5910(21667)   (Show Source):
You can put this solution on YOUR website!
3x-2y=5

3(y+10)-2y=5

3y+30-2y=5

y+30=5

y=5-30

y=-25
--------------------------

x=y+10

x=-25+10

x=-15

So the solutions are x = -10 and y = -25
-------------------------------------------------------------------------------------------------
If you need more help, email me at jim_thompson5910@hotmail.com

Also, please consider visiting my website: http://www.freewebs.com/jimthompson5910/home.html and making a donation. Thank you

Jim
-------------------------------------------------------------------------------------------------

Question 568510: What the x and the y in substitution system of equations. 3x+y=9 y=-5x+9 show details please.
Answer by jim_thompson5910(21667)   (Show Source):
You can put this solution on YOUR website!
3x+y=9

3x+(-5x+9)=9

3x-5x+9=9

-2x+9=9

-2x=9-9

-2x=0

x=0/(-2)

x=0

--------------------------
y = -5x+9

y = -5(0)+9

y = 0+9

y = 9

So the solutions are x = 0 and y = 9
-------------------------------------------------------------------------------------------------
If you need more help, email me at jim_thompson5910@hotmail.com

Also, please consider visiting my website: http://www.freewebs.com/jimthompson5910/home.html and making a donation. Thank you

Jim
-------------------------------------------------------------------------------------------------

Question 568268: how do you make a system of equations out of a word problem?
Answer by mananth(10539)   (Show Source):
You can put this solution on YOUR website!
Making a system of equations from a word problem is very easy and you have to read slowly and in parts.
2000 tickets were sold in an exhibition on Saturday. The cost of a ticket for an adult is $4 and for a child is $2. The total amount collected on Saturday was $6400. Find the number of adult tickets and child tickets sold on Saturday.

1. Generally there will will be two conditions in a problem. I will explain with the help of the problem
2. First find out what we have to find out in the problem.
In the problem we have to find the number of adult tickets & the number of child tickets sold.
Assume one as x numbers and the other as y numbers
let adult tickets sold be x and child tickets sold be y.
3. Read the first condition. It says total tickets sold = 2000
so x+y =2000 ------------------------(1)
4. Read the second condition. It gives the cost of each adult ticket and the cost of each child ticket.
5. there are x adults and y children. Adult ticket is $4 & child ticket is $2
The amount obtained from selling these tickets is $6400
amount from sale of adult tickets + the amount obtained from child tickets = total money accrued.
one adult ticket cost $4 so amount = 4x
one child ticket costs $2 so amount = 2y
4x+2y= 6400
Now you have two equations to solve for x & y.
The equations are
x+y =2000
4x+2y=6400
Solve for x & y and you have walked through the problem.
m.ananth@hotmail.ca

Question 567964: x+y=7
x-y=3
Answer by jim_thompson5910(21667)   (Show Source):
You can put this solution on YOUR website!

Start with the given system of equations:

Add the equations together. You can do this by simply adding the two left sides and the two right sides separately like this:

Group like terms.

Combine like terms.

Simplify.

Divide both sides by to isolate .

Reduce.

------------------------------------------------------------------

Now go back to the first equation.

Plug in .

Subtract from both sides.

Combine like terms on the right side.

So the solutions are and .

Which form the ordered pair .

This means that the system is consistent and independent.

Notice when we graph the equations, we see that they intersect at . So this visually verifies our answer.

Graph of (red) and (green)

Question 567960: Can you do this for me please
5[2-3(6x-1)]
Im not sure how you do this
Found 2 solutions by Theo, Earlsdon:
Answer by Theo(2967)   (Show Source):
You can put this solution on YOUR website!
5[2-3(6x-1)]
you need to resolve -3(6x-1) first.
that becomes -3 * 6x - 3*-1 which becomes:
-18x + 3
your equation becomes:
5(2-18x+3)
combine like terms to get:
5(-18x+5)
simplify to get:
-90x + 25
that should be your answer.

to confirm that this answer is good, let x be any value that's easy to calculate and then solve the original equation and the final equation using that value of x.

if the answer from the original equation is the same as the answer from the final equation, then you did good.

in this case, i'll let x = 2.
the original equation is:
5(2-3(6x-1))
replace x with 2 and the equation becomes:
5(2-3(6*2-1)) which becomes:
5(2-3(12-1)) which becomes:
5(2-3(11) which becomes:
5(2-33) which becomes:
5(-31) which becomes:
-155

the final equation is:
-90x+25
replace x with 2 to get:
-90*2+25
simplify to get:
-180+25
simplify further to get:
-155

answers from the original equation and the final equation are the same so you can reasonably assume that the answer is correct.
final equation is -90x+24

Answer by Earlsdon(6098)   (Show Source):
You can put this solution on YOUR website!
Simplify(?):
5[2-3(6x-1)] First, apply the distributive property to the parentheses inside the brackets.
5[2-3*6x-(-3)*(1)] Simplify the inside of the brackets.
5[2-18x+3] = 5[5-18x] Now apply the distributive property again.
5*5-5*18x = 25-90x

Question 567938: after 12 years a man will be 3 times as old as he was 4 years ago. find his present age
Answer by stanbon(48510)   (Show Source):
You can put this solution on YOUR website!
after 12 years a man will be 3 times as old as he was 4 years ago. find his present age
----
Let his current age be "x":
Equation:
x+12 = 3(x-4)
x + 12 = 3x -12
2x = 24
x = 12 yrs old
======================
Cheers,
Stan H.
======================

Question 567872: T 10:15 P.M., a train left Petersburg, Virginia, travelling east at 40 mi/h. Two hours later, another train left the same station travelling west at 35 mi/h. At what time will the trains be 230 mi apart?
Answer by mananth(10539)   (Show Source):
You can put this solution on YOUR website!
towards east train - 10:15 ----40 mph
Towards Weat -----35 mph----12:15
in 2 hours East bound train would have traveled 80 miles before west bound train starts.
Distance they to be apart = 230.
230-80 = 150 miles is the distance to be covered.
add up speeds 35+40 =75 mph
t=d/r
150/75 = 2 hours
they will be 230 miles apart at 2:15 pm.( 2hours after west bound trains leaves)

Question 567653: I need help with this (solving systems).
The Science Club needs to rent a bus for a field tripe. M.S. Buses charges a $40 rental fee, plus $2 per mile. C.B. Buses charges a $20 rental fee, plus $3 per mile. For what number of miles will the total be the same? What will the charge be?
How would I solve this problem? Thank you for the help.
Answer by ankor@dixie-net.com(12684)   (Show Source):
You can put this solution on YOUR website!
The Science Club needs to rent a bus for a field tripe. M.S. Buses charges a $40 rental fee, plus $2 per mile. C.B. Buses charges a $20 rental fee, plus $3 per mile. For what number of miles will the total be the same? What will the charge be?
How would I solve this problem?
Write a cost equation for each statement and make them equal to each other
:
Let m = no, of miles for this to be true
:
" M.S. Buses charges a $40 rental fee, plus $2 per mile.
C = 2m + 40
:
"C.B. Buses charges a $20 rental fee, plus $3 per mile."
C = 3m + 20
:
3m + 20 = 2m + 40
now just solve for m, then find the cost by replacing m with that value in both equations.
If you did it right, they should be equal.
;
Let me know if you have difficulty with this.

Question 567611: 7x+2y=-13
-3x-8y=-23 using the substitution method
Answer by stanbon(48510)   (Show Source):
You can put this solution on YOUR website!
7x+2y=-13
-3x-8y=-23
using the substitution method
-----------
Modify:
y = -(7x+13)/2
3x + 8y = 23
------------------------
Substitute for "y" and solve for "x":
3x - 8[(7x+13)/2] = 23
--------------------
6x-8(7x+13) = 46
6x-56x-104 = 46
-50x = 150
x = -3
----
Solve for "y":
y = -(7x+13)/2
y = -(-21+13)/2
y = -(-8)/2
y = 4
=====================
Cheers,
Stan H.
================

Question 567547: Are the graphs of the lines in each pair parallel? Explain.
y = -3/2x + 2
3x + 2y = 8
Answer by lwsshak3(2907)   (Show Source):
You can put this solution on YOUR website!
Are the graphs of the lines in each pair parallel? Explain.
y = -3/2x + 2
3x + 2y = 8
**
Standard form of equation for a straight line: y=mx+b, m=slope, b=y-intercept
Rewrite given equations in standard form:
First equation: y=-3x/2+2
Second equation:
3x + 2y = 8
2y=-3x+8
y=-3x/2+4
..
As you can see, both lines have the same slope but different x-intercepts, therefore, lines are parallel to each other

Question 567539: -294/19-2x=-10.5
Answer by unlockmath(1120)   (Show Source):
You can put this solution on YOUR website!
Hello,
With this one multiply both sides by 19 to get:
-294-38x=-199.5
Add 294 to get:
-38x=94.5
x=-2 37/76
Make sense?
RJ
www.math-unlock.com

Question 567239: Answer graphically
2x+3y = 0
x+5y = 7
Answer by mananth(10539)   (Show Source):
You can put this solution on YOUR website!
2x+3y = 0.......................(1)
x+5y = 7........................(2)

Find the Y & X intercepts of the two lines by plugging x=0, & y=0
equation1
when x= 0, y= 0 ( 0, , 0 )
when y = 0, x= 0 ( 0 , 0, )
Equation 2
when x= 0, y= 1.4 ( 0, , 1.4 )
when y = 0, x= 7 ( 7 , 0, )

The solution is (-3,2)

Question 567190: Scenario: Gas Mileage of Cars
A BMW 128ci mile per gallon is 18. The Mercedes-Benz C300 mile per gallon is 19. It cost $20.83 for the BMW to travel 100 miles. It cost $19.73 for the Mercedes-Benz to travel 100 miles. The price for a gallon of gas is $3.75. How many gallons does it take to travel 100 miles for each vehicle?
Also, what are the equations?
(solve by elimination, and show your work)
Answer by stanbon(48510)   (Show Source):
You can put this solution on YOUR website!
Scenario: Gas Mileage of Cars
A BMW 128ci mile per gallon is 18.
---
100 miles/18 mpgallon = 5.5555 gallons
--------------------
The Mercedes-Benz C300 mile per gallon is 19.
100 miles/19 mpgallon = 5.2632 gallons
---------------------------
Cheers,
Stan H.
----
You don't need the cost per gallon information.

It cost $20.83 for the BMW to travel 100 miles. It cost $19.73 for the Mercedes-Benz to travel 100 miles. The price for a gallon of gas is $3.75. How many gallons does it take to travel 100 miles for each vehicle?

Question 567119: Birdseed costs $0.59 a pound and sunflower seeds cost %0.89. Angela's pet store wishes to make a 40-pound mixture of birdseed and sunflower seeds that sells for $0.76 per pound. How many pounds of each type of seeds should she use?
Please help me solve this application problem for systems of linear equations!
Answer by josmiceli(6769)   (Show Source):
You can put this solution on YOUR website!
Let = pounds of birdseed needed
Let = pounds of sunflower seeds needed
given:
(1)
(2)
---------------------------
(2)
(2)
(2)
Multiply both sides of (1) by
and subtract (1) from (2)
(2)
(1)

and
(1)
(1)
17 and 1/3 pounds of birdseed are needed
22 and 2/3 pounds of sunflower seed are needed
check answer:
(2)
(2)
(2)
(2)
close enough, error due to rounding off

Question 567039: Line L has equation y= -5x-15. Line m has equation y=x-3. Find the point of intersection. Can you also please show your work to get your answer.
Answer by mananth(10539)   (Show Source):
You can put this solution on YOUR website!
y= -5x-15.
y=x-3
Find the Y & X intercepts of the two lines by plugging x=0, & y=0
equation1
when x= 0, y= -15 ( 0, , -15 )
when y = 0, x= -3 ( -3 , 0, )
Equation 2
when x= 0, y= -3 ( 0, , -3 )
when y = 0, x= 3 ( 3 , 0, )

the solution is (-2,-5)

Question 567023: I'm having trouble with a math problem about systems of linear equations. FInd out the values of x and y and please show your work.
7x+3y=1
4x-y=6
I thank you for the help.
Answer by stanbon(48510)   (Show Source):
You can put this solution on YOUR website!
7x+3y=1
4x-y=6
----
Multiply thru the bottom equation by 3:
-------
7x + 3y = 1
12x -3y = 18
---------------------
Add and solve for "x":
19x = 19
x = 1
----
Solve for "y":
4x-y = 6
4 - y = 6
y = -2
==================
Cheers,
Stan H.
===================

Question 566807: Solve for y
y = 2(-1/5) + 9
Answer by jim_thompson5910(21667)   (Show Source):
You can put this solution on YOUR website!
y = 2(-1/5) + 9

y = (2/1)(-1/5) + 9

y = (2*-1)/(1*5) + 9

y = -2/5 + 9

y = -2/5 + (9/1)*(5/5)

y = -2/5 + (9*5)/(1*5)

y = -2/5 + 45/5

y = (-2 + 45)/5

y = 43/5

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Jim
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Question 566738: What are the coordinates of the vertex of the graph of f(x) = 2|x| + 4?

i chose (-2,4)
Answer by jim_thompson5910(21667)   (Show Source):
You can put this solution on YOUR website!
The vertex of f(x) = a|x-h| + k is (h,k)

In the case of f(x) = 2|x| + 4, which is really f(x) = 2|x-0| + 4, we see that h = 0 and k = 4

So the vertex is (0, 4)

-------------------------------------------------------------------------------------------------
If you need more help, email me at jim_thompson5910@hotmail.com

Also, please consider visiting my website: http://www.freewebs.com/jimthompson5910/home.html and making a donation. Thank you

Jim
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Question 566795: Solve system of equation by the substitution method.
{y = 2x + 9
{y = 7x + 10
Answer by solver91311(12117)   (Show Source):
You can put this solution on YOUR website!

So

Solve for , then substitute the derived value for into either of the original equations and then solve for

John

My calculator said it, I believe it, that settles it

Question 566688: https://takeexam.next.ecollege.com/ec/pub/K12Content/Courses/resources/swfs/media/Ninth_Grade/Math/Unit19184/Lesson73197/UT2B_stem.gif

What is the slope of the line? I solved this and got 5/2...

Answer by Alan3354(21550)   (Show Source):
You can put this solution on YOUR website!
https://takeexam.next.ecollege.com/ec/pub/K12Content/Courses/resources/swfs/media/Ninth_Grade/Math/Unit19184/Lesson73197/UT2B_stem.gif

What is the slope of the line? I solved this and got 5/2...
====================================
I got this:
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Question 566470: 2x+y=5
2x+y=1 substatution

Answer by mananth(10539)   (Show Source):
You can put this solution on YOUR website!
2 x + 1 y = 5 .............1
1 y = 1 -2 x ---------2
/ 1 =
y = 1 -2 x
Substitute y in (1)
2 x + 1 ( 1 -2 x ) =
2 x + 1 + -2 x = 5
2 x -2 x = 5 -1
0 x = 4
/ 0
x= undefined
So the system has no solution. The lines are parallel

Question 566186: I tried to use every system to solve these problems... I have an "a" and a "b" in each problem

A: x+5y = -15
y = 1/5x + 1

[ I got (-8, -1.2)for my answer]

B: 2x - 3y = -27
-3x + 2y = 23
[ I got -3 for my answer]
Answer by solver91311(12117)   (Show Source):
You can put this solution on YOUR website!

This one is set up for Substitution, but can easily be done by Elimination.

Substitution solution:

The second equation defines in terms of , so substitute the RHS expression from the second equation in place of in the first equation:

Solve for , then substitute the value back into either original equation (I suggest the second one since it gives you directly) and solve for

Elimination solution:

The first equation is already in Standard Form, i.e. where A, B, and C are integers. Put the second equation into Standard Form.

Now add the two equations, term by term which will eliminate the variable, leaving you with a single equation in . Solve that and substitute back.

John

My calculator said it, I believe it, that settles it