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

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

Question 549115: 2(w+4)=-4(2w-1)+4w
Click here to see answer by rfer(12660)

Question 549195: what is the solution to the equation: 2(x-5)^2=642(x-5)^2=64
Click here to see answer by mananth(12270)

Question 549363: Invert the matrix by computing the adjoint matrix and the determinant:
-1 1 3
0 0 -1
2 0 1
The answer is supposed to be:
0 1/2 1/2
1 7/2 1/2
0 -1 0
I want to know the method please
Click here to see answer by mathie123(224)

Question 549368: Déterminer la valeur de K pour que la matrice suivante sois inversible:
K 3 K
8 6 8
1 2 3
Thanks
Click here to see answer by stanbon(57347)

Question 549368: Déterminer la valeur de K pour que la matrice suivante sois inversible:
K 3 K
8 6 8
1 2 3
Thanks
Click here to see answer by Alan3354(30993)

Question 549381: under what conditions it has been following matrix equality?
( x y) * (1 1) = (1 1) * (x y)
( z w) (0 1) .... (0 1) (z w)
Answer: provided that z = 0 and x = w
How? Thank you
Click here to see answer by stanbon(57347)

Question 549625: Inverse the matrix with row reduced echelon form
1, 3, 4
3, -1, 6
4, 2, 1
The answer is supposed to be
-13/90, 1/18, 11/45
7/30, -1/6, 1/15
1/9, //9, -1/9
Click here to see answer by solver91311(16885)

Question 549656: Determine the values of K for which the following system has a nonzero solution:
Kx + Ky = 0
4x + 2Ky = 0
The official answer is K=0 and K=2
Help me please!
Click here to see answer by ankor@dixie-net.com(15652)

Question 549621: reduce the matrix in the form of low level:
1 -2 3 -1
2 -1 2 2
3 1 2 3
the answer is supposed to be
1 0 0 15/7
0 1 0 -4/7
0 0 1 -10/7

Click here to see answer by KMST(1868)

Question 549765: Determine x, y and z for the matrix equation holds:
x,y * 0,1 = 6,13
z,4 * 3,4 = 12,13
Thanks
Click here to see answer by mathie123(224)

Question 549765: Determine x, y and z for the matrix equation holds:
x,y * 0,1 = 6,13
z,4 * 3,4 = 12,13
Thanks
Click here to see answer by Alan3354(30993)

Question 549766: Determine the values of K for which the following system has a nonzero solution:
Kx + Ky = 0 4x + 2Ky = 0
The official answer is K=0 and K=2 but I don't know how to do this. Help me please!
Click here to see answer by solver91311(16885)

Question 549768: Tell how to determine whether the system has a unique solution, and solve it with the Cramer method:
ax + by = c
dx + ey = f
The answer is: the system has a unique solution if:
delta = ae - bd not equal to 0
and the solution is:
x = (ce - bf) / (ae - bd)
y = (af - cd) / (ae - bd)
How do we explain that?

Click here to see answer by Edwin McCravy(8909)

Question 549763: calculate the cofactor of the element 9 of this determinant
1 2 3 4
6 7 8 9
-1 -2 -3 -4
-6 -7 -8 -9
Help me please. Thank you
Click here to see answer by mathie123(224)

Question 550088: calculate the cofactor of the element 9 of this determinant:
1 2 3 4
6 7 8 9
-1 -2 -3 -4
-6 -7 -8 -9
Thank you and Merry Christmas
Click here to see answer by Alan3354(30993)

Question 549984: X-2y+3t-2w=0
3x-7y-2t+4w=0
4x+3y+5t+3w=0
Click here to see answer by Alan3354(30993)

Question 549623: Determine x, y and z for the matrix equation holds:
x,y*0,1=6,13
z,4*3,4=12,13
Click here to see answer by Edwin McCravy(8909)

Question 550120: if -3 < f < 4 and -2 < g < 1,then what is the range of possible values of fg.
Click here to see answer by Edwin McCravy(8909)

Question 550466: X+y+z=9
2x+y+3z=12
x-3y-3z=9
Using the cramer's rule how do you solve for Y ?
Click here to see answer by jim_thompson5910(28595)

Question 550656: 2x-y=-8
x+3y=6
Using cramer's rule how do you solve for x ?
Click here to see answer by jim_thompson5910(28595)

Question 551600: I am stuck on how I'm suppose to find the determinant and use the determinant to write an expression. Can you please explain how to find the determinant. Thank you.
Matrix: 4 x
10 15
Question: Write an expression for the value of the determinant of the above matrix.

Click here to see answer by jim_thompson5910(28595)

Question 551877: use the echelon method to solve:
x+y=16
6x-y=33
cant seem to get it right
Click here to see answer by KMST(1868)

Question 552345: Solve the following systems of equations:
x+2y+3z+4s+5t=87
17z-5y+203.5=-(t+5s)
4t+23s-14z+21y+13x=17.5
8y+4z+2s+10t=30x
7.5x+8y+10t=18z+9s+738
I need helping showing work on how to get these answers.
Click here to see answer by Alan3354(30993)

Question 552939: The matrix (-3 x -top- 2 2/3 -bottom-) has no inverse. I need to find the value of x.

It'd be great if you could explain it, not just give the answer so that I know how to do it in the future. Been trying for hours, some help would be greatly appreciated.
Thanks!
Click here to see answer by KMST(1868)

Question 553450: solve the following set of equations
2x+3y+z=13
3x+2y+4z=17
4x+5y+2z=24
Click here to see answer by Theo(3464)

Question 555127: find the products of the following equation in clock arithmetic: 12 x 3
Click here to see answer by Alan3354(30993)

Question 555189: Multiply matrix by matrix
Click here to see answer by Edwin McCravy(8909)

Question 556198: 2 14
y= - x + --
3 3
14
x=0,y= --
3
Click here to see answer by stanbon(57347)

Question 556199: integral 9x+4
----- dx
x2-7x+15
Click here to see answer by stanbon(57347)

Question 557023: thirty buliding operatives employed on a construction site work a 37 hour week. if the 30 operatives comprise tradesmen earning £4.75/ hour and labourers earning £4.25/ hour, how many tradesmen and how many labourers are there if the weekly bill is £5124.50. using matrices?
Click here to see answer by KMST(1868)

Question 557397: rank of the matrix ⎡
4 5 6 7
3 4 5 6
2 3 4 5
1 2 3 4
Click here to see answer by Edwin McCravy(8909)

Question 558333: perform matrix row operation and write the new matrix
1 2 2 2
0 1 -1 2 -5R2+R3
0 5 4 1
Click here to see answer by Edwin McCravy(8909)

Question 558568: find the solution for x, y, and z
x - y - 2z = -1
x + 2y + z = 5
5x + 4y - z = 13
I found:
x = 1 + k
y = 2 - k
z = k
Click here to see answer by Edwin McCravy(8909)

Question 560095: Solve the following system of equations, using the augmented matrix method. You must reduce the matrix to its row reduced echelon form and write out the complete solution to the system.
x+2y-z= -3
3x+y+z=8
2x-2y+2z=12
Click here to see answer by solver91311(16885)

Question 560099: find the inverse of the following matrices.
1 1 1 1
1 2 -1 2
1 -1 2 1
1 3 3 2
Click here to see answer by Edwin McCravy(8909)

Question 561861: Could you give me about six matrices with solutions of 5,9,10,12,6, and 18?
Click here to see answer by Edwin McCravy(8909)

Question 563956: 2 3
0 -1
1 4
what are the dimensions?
Click here to see answer by TutorDelphia(193)

Question 564048: 3x-5y+4z=43
3x-2y-2z=10
x-y+3z=25
Click here to see answer by stanbon(57347)

Question 564321: What are the w, x, y, and z values using this matrix?
1 1 1 1 4
0 1 4 3 8
0 0 1 3/5 9/5
0 0 0 1 -2
Click here to see answer by Edwin McCravy(8909)

Question 565135: solve the system using the elimination method with work shown.
2x+6y=17
2x-10y=9
Click here to see answer by mananth(12270)

Question 565133: Solve the system using any algebraic method with work shown.
2x+6y=17
2x-10y=9
Click here to see answer by mananth(12270)

Question 567326: 3x-2y=2
2x-y=2

Click here to see answer by Alan3354(30993)

Question 567343: x + y = 3k
x - y = k
The solution of the system shown is _____.
Click here to see answer by Edwin McCravy(8909)

Question 567371: There were 510 people at a play. The admission price was 2 for adults and 1 for children. The admission receipts were 810. How many adults and how many children attended?
Click here to see answer by Maths68(1474)

Question 567404: Solve the system of equations by using the inverse of the coefficient matrix.
X+2y=4
2x-3y=1
Click here to see answer by Edwin McCravy(8909)

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