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

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

Question 298457: whAT IS A DETERMINANT?
Click here to see answer by user_dude2008(1862)

Question 299512: What is the mtriz B and how do I identify the matrix elemnet b23?
B=[-1 2 5 0]
-5 0 9 7
9 12 8 -1
8 -5 0 6

Refer to matrix B and identify the matrix element b23?
A) -5
B) 0
C) 9
D) 8
Click here to see answer by jim_thompson5910(35256)

Question 300732: 1. Using matrices solve the following system of equations:

2/x-3/y+3/z=10
1/x+1/y+1/z=10
3/x-1/y+2/z=13
Click here to see answer by Fombitz(32388)

Question 301280: I need help with this problem today. Please help me! I believe that you can multiply the following problem, I just don't know the definition of why:
Can these matrices be multiplied? Why or why not? [2 /4 /0][3,0 /-2,3 /1,2]
I don't have to multiply them I just have to know wither or not you can and why you can or can't?

Click here to see answer by Edwin McCravy(20054)

Question 302903: How do I solve 64=(1/16)^x
Click here to see answer by Alan3354(69443)

Question 305288: Hi all, I was hoping someone would explain to me how to write the matrix below (B) in terms of matrix (A).
A =
(2 0 3)
(0 1 0)
(1 0 1)
B =
(-1 0 3)
(0 1 0)
(1 0 -2)
I have solved the product of AB, and I am meant to use this to write B in terms of A.
Product AB =
(1 0 0)
(0 1 0)
(0 0 1)
Any help would be great.

Click here to see answer by Fombitz(32388)

Question 305379: b-1/b-2=(b-2)/(b+2) + (1)/(b-2)
Click here to see answer by Fombitz(32388)

Question 305444: For what value(s) of k is
x1 - x2 = 3k
-2x1 + 3x2 = k - 2
consistent?
Click here to see answer by Fombitz(32388)

Question 305450: For what value(s) of k is
x1 - x2 = 3k
-2x1 + 3x2 = k - 2
consistent?
Click here to see answer by Fombitz(32388)

Question 305661: Hi again, I thought i'd rephrase my question from yesterday and make it smaller/easier to understand.
For the following system of equations:
9.5 -8 = 27
-8 + 10 = -26
express the system in matrix form.
Would that just be:
(9.5 -8 27)
(-8 10 -26)
???????
Thanks for your help,
-Nick.
Click here to see answer by Alan3354(69443)

Question 305691: How do you multiply 2x2 and 3x3 matrices?
Click here to see answer by Fombitz(32388)

Question 306382: Solve the system of equations using matrices.
3a- b - 4c= 7
2a- b + 3c= -2
a+ 2b + 4c=4
The solution set is {_,_,_}
Click here to see answer by Fombitz(32388)

Question 306384: Solve the system using matrices. Express the solution set as {w,x,y,z}
w - x + y + z = -5
2w - x - 5y + 2z = -29
3w + x - 3y - 3z= 5
-w + 3x + y + 3z = -5
The solution set is {_,_,_}
Click here to see answer by Fombitz(32388)

Question 306408: Use Gaussian elimination to solve the system
w + z = 380
w + x = 600
x - y = 170
y - z = 50
The solution set is {_,_,_}
Click here to see answer by JBarnum(2146)

Question 306604: Hi all, Im slightly confused with answering this question because I cant answer part b) with the matrix I get for part a). (See below)
The current of I1 and I2 are connected by the equations:
9.5(I1) - 8(I2) = 27
-8)I1 + 10(I2) = -26
a) Express this system of equations in Matrix form.
b) Solve the system of equations for the currents I1 and I2 using the inverse matrix.
You cant solve for the inverese of an non-square matrix, so how do I solve for I1 and I2?
Any help would be great.

Click here to see answer by themathtutor2009(81)

Question 306776: Solve the system using matrices.
x+5y=0
x+6y+z=1
-5x-y-z=74
The solution set is [_,_,_,]
Click here to see answer by Fombitz(32388)

Question 306763: Solve the matrix equation B-X=3A for X if
A=[3 -6] and B=[3 -6]
[4 4] [2 0]
[ 8 9] [2 -1]
x= [_ _]
[_ _]
[_ _]

Click here to see answer by Fombitz(32388)

Question 306818: Solve the system of equations to the right using matrices. Use Gaussian elimination with back substitution or Gauss Jordan elimination.
x + y + z= 9
x - y - z= -7
x -y + z = 1
The solution set is [_, _, _]
Click here to see answer by JBarnum(2146)

Question 307330: Let X, Y and Z be matrices of sizes 2x3, 4x3 and 1x4, respectively. Then the size of (XY)^T(Z)^T (where ^T denotes transpose of a matrix) is (2x1)
The answer to the question is 2x1, but I don't understand how to get that answer.

Click here to see answer by jim_thompson5910(35256)

Question 309491: Solve the system
x+y+z=6
x-y+z=0
x-y-z=-2
find the z value of the solution
Click here to see answer by Alan3354(69443)

Question 309493: if the earth's population today is 682,386,000,000 and the growth rate of that population is 2% per year, how long will it take(in years) for the population to increase to 10 times its present value
Click here to see answer by Alan3354(69443)

Question 310763: how do you use cramers rule to solve ( 4x-3y=-10) ?

Click here to see answer by nyc_function(2741)

Question 310760: how do i use cramers rule to solve ( -y+z=-1) ?

Click here to see answer by nyc_function(2741)

Question 313136: Let A =
-2 4
0 3
and B =
-6 2
4 0
Find the value of -4B
Click here to see answer by nyc_function(2741)

Question 313660: use log(4)3 is about 0.7925 and log(4)4 is about 1 to approximate the value of the expression log(4)96
Click here to see answer by stanbon(75887)

Question 313659: log(8)1/512=-3
write in exponential form
Click here to see answer by stanbon(75887)

Question 313661: Solve the given equation:
2+6e^(4x)=19
Click here to see answer by nerdybill(7384)

Question 315060: 2. Two cyclists start biking from a trial and start 3 hours apart. The 2nd cyclist travels at 10 mph and starts 3 hours after the 1st cyclist who is traveling at 6 mph. How much time will pass before the 2nd cyclist catches up with the 1st from the time the 2nd cyclist started biking?
Please help me with this one i got stuck Thank you
Click here to see answer by ankor@dixie-net.com(22740)

Question 315059: 1.If dan makes 20 drinks in 5 minutes and Sue makes 20 drinks in 10 minutes and Jack makes 20 drinks in 15 minutes How much time will it take all 3 of them working together to mix the 20 drinks?

Click here to see answer by ankor@dixie-net.com(22740)

Question 315233: Use Cramer's Rule, if applicable, to solve the system.
3x - 4y - 12 = 0
5x + 2y + 6 = 0
Click here to see answer by Fombitz(32388)

Question 315336: solved by eliminator method. 5x + 6y = 1; 10x +12y = 2

Click here to see answer by Fombitz(32388)

Question 316054:
Row echelon form of a system of linear equation is: 1 2 4 0 = 1 0 1 -1 2 = 2 0 0 1 3 = 0 0 0 0 1 = -2 a) write the system of equations corresponding to this matrix. us x1 x2 x3 x4 as variables. My answer: x1+2x2+4x3 = 1; x2-x3+2x4 = 2; x3+3x4 = 0; and x4= -2 b) determine whether the system is consistent or inconsistent. if consistent, give the solution. My answer: from the equations above: we know x4 = -2 so plug into x3+3(-2)=0 solve for x3 x3-6=0 +6=0+6 x3=6 we know x4=-2 and x3=6 plug into x2-(6)+2(-2)=2 x2-10=2+10 x2-10+10=12 x2=12 we know x4=-2; x3=6; x2=12 plug into x1+2(12)+4(6)=1 x1+24+24=1 x1=-48+1 x1=47 Can you let me know if this is correct? If not please help me where I have it wrong. Thank you!

Click here to see answer by jim_thompson5910(35256)

Question 316331: Use Gauss Elimination to solve the suystem of linear equations. If there is no solution say so. If there are infinitely many soultion, write each varible in terms of the parameter t.
8x+4y=8
x+5y=-8
x-y=5
Click here to see answer by Fombitz(32388)

Question 316494: is 4y=-2x-2
y=-x=1
is it consistent ? or its inconsistent?
Click here to see answer by Fombitz(32388)

Question 317011: solve for A in 1 -3 10 -6
+ 3A=
7 6 -2 6

Click here to see answer by Fombitz(32388)

Question 317135: how to express sum of a symmetric matrix
Click here to see answer by Fombitz(32388)

Question 317138: how to express sum of symmetric matrix???
Click here to see answer by Fombitz(32388)

Question 317368: Find the inverse of the following matrix, the inverse exists.
A = [2 1 0]
[0 3 1]
[1 0 -1]

Solve the matrix AX = B for x using the given matrices.
A = [1 0 2]
[-1 1 0]
[3 0 4]
B = [8]
[4]
[-6]
Click here to see answer by Fombitz(32388)

Question 317365: Let A = [ 3 2 ] and B = [ 1 0 -3 ]
[ -4 -1 ] [ 4 -2 5 ]
Find the products AB and BA, if these products exist.

Click here to see answer by nyc_function(2741)

Question 317782: A movie theater charges $7 for adults, $4.50 for children, and $1 for senior citizens. On one day, the theater sold 635 tickets and collected $2910.00 in receipts. there were 2 times as many children's tickets sold as adult tickets. How many adults, children, and senior citizens went to the movies that day? (solve using matrices. find the reduced row echelon form).
x = adults y = children and z = senior citizens
equation 1: x + y + z = 635
equation 2: $7x + $4.5y + $1z = $2910.00
equation 3: x = 2y (IS THIS RIGHT????)
equation 4: x greater than or equal to 0
equation 5: y is greater than or equal to 0
How do I figure out the third equation and solve using a matrix and putting it into reduced row echelon form? I need to know how to figure that part out, I can get it into reduced row echelon form. Your help is appreciated. Thank you!
Click here to see answer by jim_thompson5910(35256)

Question 318362: Hi, Im having great difficulty with answering these matrices questions, I am having a hard time in understanding the multiplying by rows, adding and subtracting. Here is the question.
Use augmented matrices to solve the following 2x2 systems of equations. Please show all work.
A. 3x + 4y = 11
x + 3y = 2
B. x -3y = 5
4x - 12y = 13
I know what the augmented matrices are for them both, just not able to figure out the solution.
Thanks for your help4x - 12y = 20
Click here to see answer by scott8148(6628)

Question 318985: Cheryl of Cheryl's bakery set out 18 cups of flour, 14 cups of sugar, and 13 cups of shortening for her employees to use and make some batches of chocolate chip cookies, oatmeal and peanut butter cookies. She left for the day without telling them how many batches of each type of cookie to bake. the table below gives the number of cups and ingredients required for one batch of each cookie, how many batches of each cookie type were supposed to be baked?

CC- 2 2 1
O - 1 1 2 matrix rows are: choco chip,otm, peaunt b,
PB- 4 2 1 matrix coloums : flour, sugar, shortening
SOLVE USING CRAMER'S RULE
Click here to see answer by Edwin McCravy(20054)

Question 318175: Solve the following set of equations, using matrix notations:
3x + 3y + 2z = 15
2x � 4y + 5z = 9
4x + y � 3z + = -3

Click here to see answer by Fombitz(32388)

Older solutions: 1..45, 46..90, 91..135, 136..180, 181..225, 226..270, 271..315, 316..360, 361..405, 406..450, 451..495, 496..540, 541..585, 586..630, 631..675, 676..720, 721..765, 766..810, 811..855, 856..900, 901..945, 946..990, 991..1035, 1036..1080, 1081..1125, 1126..1170, 1171..1215, 1216..1260, 1261..1305, 1306..1350, 1351..1395, 1396..1440, 1441..1485, 1486..1530, 1531..1575, 1576..1620, 1621..1665, 1666..1710, 1711..1755, 1756..1800, 1801..1845, 1846..1890, 1891..1935, 1936..1980, 1981..2025, 2026..2070, 2071..2115, 2116..2160, 2161..2205, 2206..2250, 2251..2295, 2296..2340, 2341..2385, 2386..2430, 2431..2475, 2476..2520, 2521..2565, 2566..2610, 2611..2655, 2656..2700, 2701..2745, 2746..2790, 2791..2835, 2836..2880, 2881..2925, 2926..2970, 2971..3015, 3016..3060, 3061..3105, 3106..3150, 3151..3195, 3196..3240, 3241..3285, 3286..3330, 3331..3375, 3376..3420, 3421..3465, 3466..3510, 3511..3555, 3556..3600, 3601..3645