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

Algebra ->  Matrices-and-determiminant -> Questions on Algebra: Matrices, determinant, Cramer rule answered by real tutors!      Log On

 Question 384097: How would u solve this problem by using inverse matrix: 17x+4y=76 21x+5y=94 Click here to see answer by Fombitz(25151)

 Question 384093: How would u solve this problem by using inverse matrix: 17x+4y=76 21x+5y=94 Click here to see answer by Fombitz(25151)

 Question 384240: Write the augmented matrix for the system of equations and solve the system. 2x–3y+2z=2 x+ 4y-z=9 -3x+y–5z=5 so far, I have, 2 -3 2 |2 1 4 1 |9 -3 1 -5 |5 1 4 1 |9 2 -3 2 |2 -3 1 -5 |5 1 4 1 |9 0 -11 4 |-16 0 13 -8 |32 1 4 1 |9 0 1 -1 |11 0 1 5 |-5 1 4 1 |9 0 1 -1 |11 0 0 6 |16 1 4 1 |9 0 1 -1 |11 0 0 1 |29 X+4y-z=9 y-z=11 z=29 x=-122 y=40 z=29 I plugged in my solutions to the equation to see if they are right, but didn't work. What did I do wrong? Click here to see answer by jim_thompson5910(33401)

 Question 384151: Please help me with this! Using complete sentences, explain which method you would use to solve the following system of equations and why. In your answer, include the solution to one of the variables and how you found it using the method you chose. x – 5y + 2z = 0 x + 4y – z = 12 2x – y + 3z = 10 Click here to see answer by ankor@dixie-net.com(18980)

 Question 385407: Use Cramer's rule to solve the system of equations. If D = 0, use another method to determine the solution set. x - y + 2z = 6 4x + z = 1 x + 4y + z = -15 Click here to see answer by Jk22(389)

 Question 386520: x+2y-Z=-7 2x+3y+4z=1 3x-2y+2=11 solve this system of equation using a matrix ONLY Click here to see answer by Fombitz(25151)

 Question 386980: Write an equation in slope intercept form for the line that satisfies the following condition. slope (7/13) and passes through (6,-15) Click here to see answer by mananth(14512)

 Question 387098: Question: Assume A and B are invertible matrices. (a) Find X in the following relation AXB+C=I, where I is the identity matrix. Thank-you for your help. Click here to see answer by user_dude2008(1861)

 Question 387103: how do i turn this word problem into a linear system of equations? and as a matrix equation? the problem: you have 20,000 to invest inn three types of stocks. you expect the annual returns on stock x, stock y, and stock z to be 12%, 10% and 6% as respectively. you want to combine investment in stock y and z to be 3x the amount invested in stock x. you want your overall annual return to be 9% Click here to see answer by stanbon(69061)

 Question 387201: Cramer Rule: 2x+4y=10 3x+5y=14 Click here to see answer by jim_thompson5910(33401)

 Question 387934: Solve using Cramer's Rule: 3x + 5y = 1 4x - 3y = 11 Click here to see answer by robertb(4061)

 Question 389001: Please help me solve this problem. Find the solutions for x, y, and z: x - y - 2z = -1 x + 2y + z = 5 5x +4y - z = 13 Click here to see answer by haileytucki(390)

 Question 389000: Please help me solve this problem. Find the solutions for x, y, and z: x + 2y - z = 5 2x + y + z = 1 x - y + z = -1 Click here to see answer by haileytucki(390)

 Question 389009: Please help me solve this problem. What is the value of the game represented by the following matrix: 5 1 2 8 0 -4 4 1 3 Click here to see answer by haileytucki(390)

 Question 389010: Please help me solve this problem. What percent of the time would the row player play row 1 in a mixed strategy for the following game matrix? 10 5 6 12 Click here to see answer by haileytucki(390)

 Question 389283: 1. If matrix A = [2 -4] and matrix B= [-2 5 0] [3 1] [-1 0] a) give the dimensions of A b) give the dimensions of B * the matrix a looks like this (i dont know how to make the big blocks) : 2 -4 3 1 -1 0 in light of the dimensions above, 1.can you multiply A x B? 2.if so, what are the dimensions of the result 3.give the result if possible. Click here to see answer by ewatrrr(22107)

 Question 389282: 1. If matrix A = [2 -4] and matrix B= [-2 5 0] [3 1] [-1 0] a) give the dimensions of A b) give the dimensions of B * the matrix a looks like this (i dont know how to make the big blocks) : 2 -4 3 1 -1 0 Click here to see answer by ewatrrr(22107)

 Question 389307: how many solutions exist? 1. 3x-y=7 6x-2y=6 are the equations : consistent/inconsistent/dependent graphs of the lines are : intersect/parallel/coincide 2. 3x+2y=5 -x+5y=7 are the equations : consistent/inconsistent/dependent graphs of the lines are : intersect/parallel/coincide 3. -x-2y=-3 3x+6y=9 are the equations : consistent/inconsistent/dependent graphs of the lines are : intersect/parallel/coincide Click here to see answer by robertb(4061)

 Question 389348: find the value of the determinant. 1 4 7 -2 5 2 2 5 -2 Click here to see answer by haileytucki(390)

 Question 389305: use Cramer's rule : 3x+2y-z=0 2x-1y+3z=-1 -2x+2z=4 Click here to see answer by haileytucki(390)

 Question 389536: 1. If A= [2 -4] [-2 5] FIND A^-1 2. use the question & answer above to calculate A X A^-1 Click here to see answer by haileytucki(390)

 Question 389758: What is Matrices, determinant, and the cramer rule? Click here to see answer by stanbon(69061)

 Question 389772: Can you please help me with this problem? Solve the following systems of equations using matrix multiplication. 2x-5y+7z=4 3x+y-12z=-8 5x+2y-4z=3 Click here to see answer by Edwin McCravy(13211)

 Question 389707: 1. IF : [3 0 -3] [2 1 0] = 9, [0 -2 -1] then find: [6 0 -3] [4 1 0] [0 -2 -1] 2. IF : [3 0 -3] [2 1 0] = 9, [0 -2 -1] then find : [3 0 -3] [(2+0) (1-2) (0-1)] [0 -2 -1] Click here to see answer by Edwin McCravy(13211)

 Question 390390: a triangle has an area of 6 square units. I t has vertices with coordinates(1,-3),(4,2) and a point on the x-axis. find all possible coordinates for this point Click here to see answer by robertb(4061)

 Question 390673: what is the inverse of matrix R? Is it P, Q, S Click here to see answer by Alan3354(47455)

 Question 390953: What can be the result of adding this 2 equations? 4x+y=7 X-y=-2 Click here to see answer by ewatrrr(22107)

 Question 391615: find the determinant of [x y] [z w] Click here to see answer by robertb(4061)

 Question 391708: If x is 2,3,4 and Y is 11,49,123 what is the rule? I have tried everything and am stumped. I do believe that exponents is the way to answer this equation, but still can not figure it out. Please Help!? Click here to see answer by Edwin McCravy(13211)

 Question 391693: how do i find the unit vectors in the same direction as U and V if U=(-3, 9 -3) and V=(4, -1, 7) Click here to see answer by Edwin McCravy(13211)

 Question 391835: 3x+y+2z=80 x+2y-z=10 2x-y+3z=70 solve please Click here to see answer by stanbon(69061)

 Question 391924: Given the linear system 3x+4y=s 6x+8y=t (a)determine particular values for s and t so that the system is consistent. (b)determine particular values for s and t so that the system is inconsistent. (c)what relationship between the values of s and t will guarantee that the system is consistent? Click here to see answer by robertb(4061)

 Question 391929: can u help me solve tis linear system using method of elimination?thanx. x+y-2z=5 2x+3y+4z=2 Click here to see answer by Alan3354(47455)

 Question 391931: Determine a solution to each of the following linear systems, using the fact that Ax=b is consistent if and only if b is a linear combination of the columns of A: {1234/2341/3412}{A/B/C/D}={20/20/20} (Hints:It is {4x3 matrix}{4x1 matrix}={3x1 matrix},slash / mean next row) P/S:I don't know how to write matrix bracket,hope you will understand Click here to see answer by stanbon(69061)

 Question 391992: I really don't know about this problem. I'm confused. I have to solve this problem by completing the square: 2x(squared)+5x-8=0 Can you help me? Please and Thank you. :) Click here to see answer by ewatrrr(22107)

 Question 391987: Please help! I need to find, if possible, the following matrices: a) AB b) BA Let A = 1 -1 1 5 0 -2 3 -2 2 Let B= 1 1 0 1 -4 5 3 -1 2 Thank you for your help! Click here to see answer by Edwin McCravy(13211)

 Question 391983: I am stuck with these martix problems! could someone please help? Here is the problem: Use Guassian elimination to find the complete solution to each system of equations, or show that none exists. Here is the system of equations: 2w-x+3y+z=0 3w+2x+4y-z=0 5w-2x-2y-z=0 2w+3x-7y-5z=0 (It almost looks like all the variables must be "0", but that can't be right!) Anyway, here is the matrix taken from the system: 2 -1 3 1 0 3 2 4 -1 0 5 -2 -2 -1 0 2 3 -7 -5 0 Ok, I need help from here, please! Thank you to whomever responds! Click here to see answer by richard1234(6688)

 Question 392357: Which matrix equation should be used to find the intersection of these two lines? 3x = 2 + 4y 2y = 6 -5x Click here to see answer by NancyLam(35)
 Question 392357: Which matrix equation should be used to find the intersection of these two lines? 3x = 2 + 4y 2y = 6 -5x Click here to see answer by robertb(4061)

 Question 392771: Please help! I need to solve the following using Cramer's Rule. The textbook doesn't do a good job of defining this, so i would be extremely grateful for any help!! solve by Cramer's Rule: 3x=7y+1 2x=3y-1 solve by Cramer's rule: x-3y+z=-2 x+2y =8 2x-y =1 Thank you for your help! Click here to see answer by stanbon(69061)

 Question 392769: Could someone please help? I need to a) write each linear equation as a matrix equation in the form of AX=B. then i have to B) solve the system using the inverse that is given for the coefficient matrix. here is the problem: The system is: x-6y+3z=11 2x-7y+3z=14 4x-12y+5z=25 The inverse of: 1 -1 1 0 2 -1 2 3 0 is.... 3 3 -1 -2 -2 1 -4 -5 2 Please help!! I have NO idea where to start! Thank you to whomever responds!!! Click here to see answer by stanbon(69061)

 Question 392758: Please help!! Am having great difficulty! The problem: Use the fact that if A= a b c d , then A^-1 = 1/ad-bc * d -b -c a to find the inverse of each matrix, if possible. Check that AA^-1=I2 and A^-1A=I2. A= 6 -3 -2 1 Thank you sooo much to whomever responds! Click here to see answer by jim_thompson5910(33401)

 Question 392754: could someone please help? I need to solve each system of equations using guassian elimination w/back substitution or guass-jordan elimination. here is the system of equations: 1st system: 3y-z=-1 x+5y-z=-4 -3x+6y+2z=11 2nd system: 3a+b-c=0 2a+3b-5c=1 a-2b+3c=-4 3rd system: 2w-3x+4y+z=7 w-x+3y-5z=10 3w+x-2y-2z=6 Thank you to the person who responds! I would be extremely grateful for your assistance!!! Click here to see answer by solver91311(20879)