Questions on Algebra: Matrices, determinant, Cramer rule answered by real tutors!

Tutors Answer Your Questions about Matrices-and-determiminant (FREE)

Question 321942: Matrices A and B are multiplicative inverses. Find X
> 2 , x <
> 1 , 2 <

> 2 , -3 <
> -1 , 2 <
Thank you.
Click here to see answer by Fombitz(32388)

Question 322329: |-2 -3 -3 3|
|-1 -2 -2 4|
| 1 2 1 1|
|-1 4 4 -2|

Click here to see answer by Fombitz(32388)

Question 322666: this is a problem!!
jose invested $600 at 7% interest. he also invested $400 at 6.5% interest at the end of the year, his money had earned $68 interest?
Click here to see answer by solver91311(24713)

Question 323046: (x)Emily and (y)Camille started from the same city and drove in opposite directions on the freeway. after 3 hours they were 354 miles apart. if they had gone in the same direction, Emily would have been 18 miles ahead of camille. how fast did each woman drive? Total distance between x and y when they traveled in opposite directions? Total distance when they traveled in the same direction?
I'm suppose to make to equations and put into matrix using cramer's rule.
Click here to see answer by galactus(183)

Question 323684: what is a dependent matrix?
what is an inconsistant matrix?
How do you can you tell?
Click here to see answer by Fombitz(32388)

Question 323727: solve the system using matrices
3x+3y+6z=,
3x+2y+2z=9,
2x+6y+14z=26
Click here to see answer by Alan3354(69443)

Question 323865: x+7y-z=6
Click here to see answer by loraine07(3)

Question 323866: 3a-b-3c=14,2a-b+3c=5,a+2b-4c=3
Click here to see answer by Fombitz(32388)

Question 323349: Need to find the inverse of a 3x3 matrix?
-2 5 -1
-1 -2 -3
3 -4 -5
Click here to see answer by Fombitz(32388)

Question 324567: find the determinant and inverse of the following matrices:
use the Gauss Jordan Method for the inverse.
1 2 3
0 1 4
0 0 8

I got the determinant, it should be 8. i would like to know if im correct.
thank you.
Click here to see answer by jim_thompson5910(35256)

Question 324865: Hello, Can someone please explain how I can determine the number of permutation for the work SELECTION the following is my answer but I am not sure if it is right. Thank you.
Determine the number of permutations of the letters of the word �SELECTION.�
ANSWER:
Number of Permutations taking all the letters at a time = 9P9
= 9! = 362880.

I am not sure what topic best fits my question.
Sorry
Click here to see answer by scott8148(6628)

Question 324812: Find x1 and x2 for(show steps involved):
[-4 5][x1]+[ 3]=[71]
[-2-4][x2] [18] [ 0]
*note* both lines are part of the same matrix equation, I didn't know how to type it as a continuous multi-line matrix bracket.
Click here to see answer by Fombitz(32388)

Question 324942: find 5A
A= 3 3/5
0 -1

Click here to see answer by Fombitz(32388)

Question 324886: 5x-3y+7=11
3x+y-2z=11
-x+2y+z=11
Using the matrix method,which row of operations can i use to solve this problem?
Click here to see answer by Fombitz(32388)

Question 326516: How can I use Cramer�s rule to solve for y in the following system of equations.
x + 4y � 2z = 3
x + 3y + 7z = 1
2x + 9y + z = 8

Click here to see answer by Alan3354(69443)

Question 326751: 2/3a+4/9b=1
3a-2b=4
Click here to see answer by Fombitz(32388)

Question 327479: I need to find the minor of a22 in the follwing 3x3 matrix. Row 1: 8,-5,8 Row 2: 4,8,6 Row 3: 0,3,-4
Click here to see answer by jim_thompson5910(35256)

Question 328247: what is the slope-intercept form of the equation of a line which contains the points (�2, �1) and (3, 4).
Click here to see answer by stanbon(75887)

Question 328246: The sum of 3 times a number and 10 is 25. what is the number??
Click here to see answer by stanbon(75887)

Question 328240: The sum of 3 times a number and 10 is 25. Find the number
Click here to see answer by stanbon(75887)

Question 328239: Identify the slope-intercept form of the equation of a line which contains the points (�2, �1) and (3, 4).
Click here to see answer by Fombitz(32388)

Question 328555: Find 5A + 3B.
A = 2 -5
-5 2
B = 5 -2
2 -5
Click here to see answer by Alan3354(69443)

Question 306159: Solve this system of equations for the values of x , y & z using the Cramer's rule
3/x - 4/y + 6/z = 1
9/x + 8/y - 12/z = 3
9/x - 4/y + 12/z = 4
Click here to see answer by tarzan234(1)

Question 328639: Use matrix inversion to solve each system of equations.
3x - 4y = -1
-2x + 3y = 3
Click here to see answer by Fombitz(32388)

Question 328638: Find the inverse of the matrix.
2 3
3 -5
Click here to see answer by Fombitz(32388)

Question 329422: I need some help in solving this problem. The current ina stream moves at a speed of 2 km/h. A boat travel 27 km upstream and 27 km downstream in a total of 17 hours. What is the speed of the boat in still water?
Click here to see answer by stanbon(75887)

Question 330377: Solve the following system of equations using the inverse matrix method.

Find x,y,z
Click here to see answer by Edwin McCravy(20054)

Question 330501: 2) Solve the following linear system using matrices:
2x-y+3z=-4
x-2y+z=-1
x-5y+2z=-3

Click here to see answer by Fombitz(32388)

Question 330776: How many negative real zeros does the function f(x) = x5 + x4 � x2 � x + 1 have?
Click here to see answer by Fombitz(32388)

Question 330981: Solve x^2-4x=1 by completing the square.
Click here to see answer by solver91311(24713)

Question 331362: i have a math problem that looks like four numbers inside these brackets that look like [ ] plus four more numbers in those brackets. how do i solve that?
Click here to see answer by Edwin McCravy(20054)

Question 331843: 9<-2.5a what the answer? and show you come up with the answer show work please.
Click here to see answer by rfer(16322)

Question 332233: Can someone show me how to use the elimination method to solve this problem. The solution says it is (4y+1,y) for any real numbers. I just don't kow how they go it. Thanks
2x-8y=2
3x-12y=3
Click here to see answer by jim_thompson5910(35256)

Question 332230: It says to use the elimination method for this problem but I don't understand what to do because it says the answers has not solution. Can someone please help. I am so confused.
2x+3y=15
8x+12y=40
Click here to see answer by Alan3354(69443)

Question 332650: Use the Gauss-Jordan Method to solve the system of equations.
x = 1 - y
2x = Z
2z = 2 - y
I am really confused by this totally and really have no idea where to start. Can someone help please.

Click here to see answer by solver91311(24713)

Question 332777: multiply both side of the equation by a common denominator to eliminate the
fractions. Then solve the system.

x/4+3y=31
2x-y/5=8
I have been struggling to try to solve this for over 4 days now and have had no luck. We are given the final answer which is (5,10) but I can not figurge out how they got to that. I need to show the work and solve the problem. Can someone please help me.

Click here to see answer by mananth(16946)

Question 332786: Multiply both side of the equation by a common denominator to eliminate the
fractions. Then solve the system.
x/5+3y=31
2x-y/5=8
I have been struggling to try to solve this for over 4 days now and have had no
luck. We are given the final answer which is (5,10) but I can not figurge out
how they got to that. I need to show the work and solve the problem. Can
someone please help me.
Click here to see answer by Earlsdon(6294)

Question 332776: I solve this by using elimination and show my work.

4x-3y=-1
x+2y=19
I need help plz. I have been trying to solve this for three days now.
Click here to see answer by Jstrasner(112)

Question 332827: evaluate the determinant 2 3
3 2
Click here to see answer by solver91311(24713)

Question 332774: I own a company that sells high-end computers; I made 2 orders from a vendor: the first one was for 1300 desktops and 400 laptops totaling $48,700. The second order was for 600 desktops and 200 laptops totaling $23,200. The receipts were not itemized. What is the cost of one desktop and one laptop?
I need to be able to show the work.
Click here to see answer by jrfrunner(365)

Question 333165: Solve by elimination:
-x+3y=6
x-9y=9
Click here to see answer by checkley77(12844)

Question 333163: Solve by elmination:
x-y=3
x+3y=3
Click here to see answer by nyc_function(2741)

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