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

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

Question 1087343: y+x=10
y+z=20
x+z=24

Click here to see answer by Fombitz(32388)

Question 1088313: The perimeter of a rectangular cutting board is 38 inches. The area is 88 in.�. What are the dimensions of the cutting board
Click here to see answer by josgarithmetic(39613)

Question 1088535: The sum of three nos,. Is 2,if twice the second no. Is added to sum of first and third ,we get 1 on adding the sum of s3cond and third no. To the five times the first, we get 6. Find the three nos.

Click here to see answer by ikleyn(52750)

Question 1088695: Solve the following system of equations.
A large curly brace opens to the right.
2 x2x
plus+
4 y4y
minus−
zz
equals=
1818
negative 4 x−4x
minus−
4 y4y
minus−
2 z2z
equals=
negative 18−18
4 x4x
plus+
8 y8y
plus+
3 z3z
equals=
16
Click here to see answer by ikleyn(52750)

Question 1089128: x-y+2=4,2x+y-32=0,x+y+z=2
Click here to see answer by mrafea(1)

Question 1089782: Hello, Could someone please help me? I am supposed to solve the problem by using the Gauss-Jordan method to solve a system of equations. Mixing solutions. *A 5% solution of a drug is to be mixed with some 15% solution and some 10% solution to get 20ml of 8% solution. The amount of 5% solution used must be 2ml more than the sum of the other two solutions. How many millimeters of each solution should be used? I know the answers are 3ml of !5%, 6ml of 10% and 11ml of 5%, but I have no idea how to "solve" using the Gauss-Jordan method! I have equations x+y+x+y+2=20, 30-3y=4(9-y) and 6+3+2. Any help would be appreciated! Thanks!
Click here to see answer by josgarithmetic(39613)

Question 1090444: if C is a 4x4 matrix and det(C) = -3, then det(2C) = -48
True or False
Click here to see answer by Fombitz(32388)

Question 1090487: 2x-y+3z=4 , x+y+z=2 , 3x+y-z=2 solve by Cramer rule
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Question 1092399: Step by step solution using Gauss method of this linear system:

Click here to see answer by MathLover1(20849)

Question 1094242: 2/3x-3/5y=-1
-1/6x+3/10y=5/2
Click here to see answer by ikleyn(52750)

Question 1094810: Determine whether the following system of equations are consistent, independent and inconsistent
t-u+2v-3w=9
4t+11v-10w=46
3t-u+8v-6w=27.
Click here to see answer by ikleyn(52750)

Question 1096191: Determine if the following system of equation are consistent or in consistent?(linear equation)
X�+3x�= 2
X� - 3x⁴=3
-2x�+3x�+2x⁴=1
3x� + 7x⁴=-5
Click here to see answer by ikleyn(52750)

Question 1097110: Out of a group of 50 companies, 18 have offices in Kenya, 26 have offices in Uganda and 26 have offices in Ethiopia. Furthermore, 11 have offices in Kenya and Uganda, 9 have offices in Kenya and Ethiopia and 13 have offices in Uganda and Ethiopia. Finally, 5 companies have offices in all the three countries. Determine how many of the 50 companies do not have offices in any of the three countries? How many companies have offices only in Kenya?
Click here to see answer by ikleyn(52750)

Question 1097901: 5x+8y-z=36
x-2y+7z=18
3x+y+z=21
Click here to see answer by Alan3354(69443)

Question 1098643: Mr Tui inherits a sum of $10,000 in Australia. He wants to invest this sum into three investments: Cooperate Bills, Cooperate Bonds and Treasury Bonds, with annual rates of 12%, 8% and 4% respectively. He wants his investment in Cooperate Bonds to be $500 more than the investment in Treasury Bonds. Use the Gauss Jordon Elimination method to find how much Mr Tui should allocate to each of his investments, in order to get an annual income of exactly $1,000.
Click here to see answer by greenestamps(13195)

Question 1099338: Please help me
Give examples to show that the following statements are wrong.
1) if (Matrix) , then A = 0 or A is an Identity matrix
2) if AX = AY, and Y is not equal to 0, the X = Y
Click here to see answer by ikleyn(52750)

Question 1099395: Please help
Suppose A, B and AB-I are non-degenerate and have same order. Prove that
(1) is non-degenerate.
(2) is non-degenerate. find the inverse of this matrix.
Click here to see answer by ikleyn(52750)

Question 1099576: Solve system of linear equations, using matrix method.
x − y +2z =7
3x +4y −5z =−5
2x − y + 3z = 12

Click here to see answer by Fombitz(32388)

Question 1099575:
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Question 1099794: A and B are two square matrices of rank 2. If |-2AB|=48, |B|=2, what is |A|?
Click here to see answer by Fombitz(32388)

Question 1099888: Solve the given system of equations by determinants.
2x-2y-5=0
4x+4=3y
Click here to see answer by richwmiller(17219)

Question 1099888: Solve the given system of equations by determinants.
2x-2y-5=0
4x+4=3y
Click here to see answer by ikleyn(52750)

Question 1100488: 2x+y-2=0;3x-y-13=0using determinantmethod
Click here to see answer by Fombitz(32388)

Question 1100488: 2x+y-2=0;3x-y-13=0using determinantmethod
Click here to see answer by ikleyn(52750)

Question 1100489: and
x -y = 1

Using 3 by 3 method solve this simultaneously
x + y + z - 2 = 0

Click here to see answer by richwmiller(17219)

Question 1100689: Kayanna decided to save the 5-cent, 10-cent, and 25-cent pieces she collected after purchase made while shopping with her father. After a period of days she had a total of 246 coins. The money value of the coins was $25.50. If the amount of 5-cent pieces was 40 less than twice the amount of 10-cent pieces.
a. Derive a system of three equations showing the information given.
b. Use Cramer's Rule to find how many of each type of coins she had.

Please assist
Click here to see answer by richwmiller(17219)

Question 1100812: |x 1 0
1 x 1
2 3 2|=−4x

Click here to see answer by Fombitz(32388)

Question 1100816: Solve for x if

X 1 0
1 X 1
2 3 2 = -4x.

Click here to see answer by greenestamps(13195)

Question 1100816: Solve for x if

X 1 0
1 X 1
2 3 2 = -4x.

Click here to see answer by josgarithmetic(39613)

Question 1101027: Parcel A and B together weigh 24 kgs, but parcel B and C together weighs only 21 kgs. When parcel A and C are paired, the combined weight is 27kgs. If the weight of parcel A is represented by a, parcel B by b and parcel C by c; derive a system of three equations for a, b and c. Using the inverse method derive the combined weight of parcel A, B and C.
Click here to see answer by ikleyn(52750)

Question 1101028: The demand and supply curves for a good are given as Pd=100-(q+4)^2 and Ps=(q+2)^2 respectively where q is in thousands. Find the equilibrium price and quantity of the good.
Click here to see answer by jorel1380(3719)

Question 1101042: If parcel A and B together weigh 24 kgs, but parcel B and C together weighs only 21 kgs.
When parcel A and C are paired, the combined weight is 27kgs. If the weight of parcel A is
represented by a, the weight of parcel C is represented by b and the weight of parcel C is
represented by c.
a. Derive a system of three equations in a, b and c.
b. Using the inverse method derive the combined weight of parcel A, B and C
Click here to see answer by jorel1380(3719)

Question 1101056: The value V of a stand-by generator after t years of depreciation is given by the formula V(t) =
57000e^−0.2t + 3500. Approximately how many years will it take for the value to depreciate to
$5,000?
Please Assist

Click here to see answer by jorel1380(3719)

Question 1101063: The value V of a stand-by generator after t years of depreciation is given by the formula V(t) =57000e^−0.2t + 3500. Approximately how many years will it take for the value to depreciate to
$5,000?
Click here to see answer by josmiceli(19441)

Question 1101242: Consider the linear system:
.
a) [2 marks] Find |A|, A is the coefficient matrix for the linear system.
b) [1 marks] Is the linear system consistent? Explain.
c) [4 marks] Is the matrix A invertible? Explain. If your answer is yes, then find the inverse.
d) [1 marks] Solve the linear system.
e) [2 marks] Change the third equation in the linear system to 2x  y  z = 0. Is the new linear system consistent? Explain your answer.

Click here to see answer by richwmiller(17219)

Question 1101239: If A and B are n�n matrices, then (A + B)(A � B) = A^2 � B^2.
Click here to see answer by Edwin McCravy(20054)

Question 1101270: AB=BA=I and AC=CA=I. Then what about B an C
a. They are equal
b. they are not equal
c. Each is equal to A
d. None

Click here to see answer by Boreal(15235)

Question 1101271: AB=BA=I and AC=CA=I. Then what about B an C
a. They are equal
b. they are not equal
c. Each is equal to A
d. None
Click here to see answer by rothauserc(4718)

Question 1101240: Q�−3: Let , and .
a) [4 marks] Find, if possible, a matrix X such that AX + B = C.
b) [4 marks] Find, if possible, a matrix Y such that (Y + BCT)-1 = A.
c) [2 marks] Find, if possible, a matrix Z such that ZA + B = C? Explain your answer.

Click here to see answer by ikleyn(52750)

Question 1101975: A message is converted into numeric form

Which of the following represents the encryption of the word,

Click here to see answer by richwmiller(17219)

Question 1101974: A message is converted into numeric form
Click here to see answer by richwmiller(17219)

Question 1101982: Please help me solve this equation:
Suppose A, B and are non-degenerate and have same order. Prove that
(1) is non-degenerate.
(2) is non-degenerate . Find the inverse of the matrix.
Click here to see answer by richwmiller(17219)

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