SOLUTION: When solving the system of equations 6x+2y=-1 and -x+10y=5 by Cramer's Rule, what are the values of D, Dx, and Dy A. D=58, Dx=20, Dy=-28 B. D=62, Dx=20, Dy=28 C. D=58, Dx=-20,

Algebra ->  Radicals -> SOLUTION: When solving the system of equations 6x+2y=-1 and -x+10y=5 by Cramer's Rule, what are the values of D, Dx, and Dy A. D=58, Dx=20, Dy=-28 B. D=62, Dx=20, Dy=28 C. D=58, Dx=-20,      Log On


   

Question 1127838: When solving the system of equations 6x+2y=-1 and -x+10y=5 by Cramer's Rule, what are the values of D, Dx, and Dy
A. D=58, Dx=20, Dy=-28
B. D=62, Dx=20, Dy=28
C. D=58, Dx=-20, Dy=-29
D. D=62, Dx--20, Dy=29
Found 2 solutions by MathLover1, ikleyn:
Answer by MathLover1(20849) About Me  (Show Source):
You can put this solution on YOUR website!
Your matrix

matrix%282%2C3%2C6%2C%092%2C%09-1%2C%0D%0A-1%2C%0910%2C%095%29


Write down the main matrix and find its determinant:


matrix%282%2C2%2C6%2C2%2C%0D%0A-1%2C10%29

D=++6%2A10-%28-1%29%2A2=60%2B2=62
+D=+62


Replace the 1st column of the main matrix with the solution vector and find its determinant:

matrix%282%2C2%2C-1%2C2%2C%0D%0A5%2C10%29

D%5Bx%5D=+-1%2A10-2%2A5=-20
+D%5Bx%5D=-20


Replace the 2nd column of the main matrix with the solution vector and find its determinant:

matrix%282%2C2%2C6%2C%09-1%2C%0D%0A-1%2C%095%29
D%5By%5D=6%2A5-%28-1%29%28-1%29=30-1=29
D%5By%5D=29


so, your answer is: D. D=62, D%5Bx%5D=-20, D%5By%5D=29


Answer by ikleyn(52756) About Me  (Show Source):
You can put this solution on YOUR website!
.

On Cramer's rule for systems of 2 equations in 2 unknowns see the lessons
    - What is a matrix?,
    - Determinant of a 2x2-matrix,
    - HOW TO solve system of linear equations in two unknowns using determinant (Cramer's rule),
    - Solving systems of linear equations in two unknowns using the Cramer's rule,
in this site.

Also,  you have this free of charge online textbook in ALGEBRA-II in this site
    - ALGEBRA-II - YOUR ONLINE TEXTBOOK.

The referred lessons are the part of this online textbook under the topic
     "2x2-Matrices, determinants, Cramer's rule for systems in two unknowns"


Save the link to this textbook together with its description

Free of charge online textbook in ALGEBRA-II
https://www.algebra.com/algebra/homework/complex/ALGEBRA-II-YOUR-ONLINE-TEXTBOOK.lesson

into your archive and use when it is needed.