x=31,y=−61
Put the equations in standard form and then use matrices to solve the system of equations.
5x+4y=1,3x−6y=2
Write the equations in matrix form.
(534−6)(xy)=(12)
Left multiply the equation by the inverse matrix of (534−6).
inverse((534−6))(534−6)(xy)=inverse((534−6))(12)
The product of a matrix and its inverse is the identity matrix.
(1001)(xy)=inverse((534−6))(12)
Multiply the matrices on the left hand side of the equal sign.
(xy)=inverse((534−6))(12)
For the 2×2 matrix (acbd), the inverse matrix is (ad−bcdad−bc−cad−bc−bad−bca), so the matrix equation can be rewritten as a matrix multiplication problem.
(xy)=(5(−6)−4×3−6−5(−6)−4×33−5(−6)−4×345(−6)−4×35)(12)
Do the arithmetic.
(xy)=(71141212−425)(12)
Multiply the matrices.
(xy)=(71+212×2141−425×2)
Do the arithmetic.
(xy)=(31−61)
Extract the matrix elements x and y.
x=31,y=−61
Answer:
3
Step-by-step explanation:
the absolute meaning of a number is never a negative number
Answer: 9/x-1
Step-by-step explanation:
Sine you are subtracting,
x-x=o
1- -8 =9 since subtracting a negative is adding a positive.
So the answer is 9/x-1
Answer:
total interest earned = $230
percent interest for the total deposited = 5.75%
Step-by-step explanation:
Account 1 : deposited = $1,000 with interest 2%/year
Account 2 : deposited = $3,000 with interest 7%/year
Interest account 1 = 2% x $1,000 = $20
Interest account 2 = 7% x $3,000 = $210
Total interest earned = 20 + 210 = $230
Total interest earned = Percent interest x Total deposited
230 = Percent interest x (1,000+3,000)
230 = Percent interest x 4,000
230 : 4000 = Percent interest
Percent interest = 230 : 4000 = 0.0575 = 5.75%
Answer:
x = 5/3
Step-by-step explanation:
pretty sure thats the answer