At Westonci.ca, we connect you with the answers you need, thanks to our active and informed community. Get quick and reliable solutions to your questions from knowledgeable professionals on our comprehensive Q&A platform. Explore comprehensive solutions to your questions from a wide range of professionals on our user-friendly platform.
Sagot :
We are given three determinants related to a system of linear equations and asked to find the values of [tex]\(x\)[/tex] and [tex]\(y\)[/tex]. Here is the step-by-step solution using these determinants:
1. Calculate the determinant of matrix [tex]\(A\)[/tex], denoted as [tex]\(|A|\)[/tex]:
[tex]\[ |A| = \left|\begin{array}{cc} 4 & -6 \\ 8 & -2 \end{array}\right| \][/tex]
The determinant of a 2x2 matrix [tex]\(\left|\begin{array}{cc} a & b \\ c & d \end{array}\right|\)[/tex] is calculated as [tex]\(ad - bc\)[/tex].
So,
[tex]\[ |A| = (4 \cdot -2) - (-6 \cdot 8) = -8 + 48 = 40 \][/tex]
2. Calculate the determinant [tex]\(|A_x|\)[/tex]:
[tex]\[ |A_x| = \left|\begin{array}{cc} 38 & -6 \\ 26 & -2 \end{array}\right| \][/tex]
Using the formula for the determinant of a 2x2 matrix,
[tex]\[ |A_x| = (38 \cdot -2) - (-6 \cdot 26) = -76 + 156 = 80 \][/tex]
3. Calculate the determinant [tex]\(|A_y|\)[/tex]:
[tex]\[ |A_y| = \left|\begin{array}{cc} 4 & 38 \\ 8 & 26 \end{array}\right| \][/tex]
Using the formula again,
[tex]\[ |A_y| = (4 \cdot 26) - (38 \cdot 8) = 104 - 304 = -200 \][/tex]
4. Use Cramer's Rule to solve for [tex]\(x\)[/tex] and [tex]\(y\)[/tex]:
According to Cramer's Rule, if [tex]\(|A|\)[/tex] is the determinant of the matrix of the system, [tex]\(|A_x|\)[/tex] and [tex]\(|A_y|\)[/tex] are the determinants obtained by replacing the columns of the matrix with the constants from the equations, then:
[tex]\[ x = \frac{|A_x|}{|A|} \][/tex]
[tex]\[ y = \frac{|A_y|}{|A|} \][/tex]
5. Calculate [tex]\(x\)[/tex]:
[tex]\[ x = \frac{|A_x|}{|A|} = \frac{80}{40} = 2.0 \][/tex]
6. Calculate [tex]\(y\)[/tex]:
[tex]\[ y = \frac{|A_y|}{|A|} = \frac{-200}{40} = -5.0 \][/tex]
So, the solution to the system of equations is [tex]\(x = 2\)[/tex] and [tex]\(y = -5\)[/tex]. Therefore, the correct answer is [tex]\(\boxed{x=2, y=-5}\)[/tex].
1. Calculate the determinant of matrix [tex]\(A\)[/tex], denoted as [tex]\(|A|\)[/tex]:
[tex]\[ |A| = \left|\begin{array}{cc} 4 & -6 \\ 8 & -2 \end{array}\right| \][/tex]
The determinant of a 2x2 matrix [tex]\(\left|\begin{array}{cc} a & b \\ c & d \end{array}\right|\)[/tex] is calculated as [tex]\(ad - bc\)[/tex].
So,
[tex]\[ |A| = (4 \cdot -2) - (-6 \cdot 8) = -8 + 48 = 40 \][/tex]
2. Calculate the determinant [tex]\(|A_x|\)[/tex]:
[tex]\[ |A_x| = \left|\begin{array}{cc} 38 & -6 \\ 26 & -2 \end{array}\right| \][/tex]
Using the formula for the determinant of a 2x2 matrix,
[tex]\[ |A_x| = (38 \cdot -2) - (-6 \cdot 26) = -76 + 156 = 80 \][/tex]
3. Calculate the determinant [tex]\(|A_y|\)[/tex]:
[tex]\[ |A_y| = \left|\begin{array}{cc} 4 & 38 \\ 8 & 26 \end{array}\right| \][/tex]
Using the formula again,
[tex]\[ |A_y| = (4 \cdot 26) - (38 \cdot 8) = 104 - 304 = -200 \][/tex]
4. Use Cramer's Rule to solve for [tex]\(x\)[/tex] and [tex]\(y\)[/tex]:
According to Cramer's Rule, if [tex]\(|A|\)[/tex] is the determinant of the matrix of the system, [tex]\(|A_x|\)[/tex] and [tex]\(|A_y|\)[/tex] are the determinants obtained by replacing the columns of the matrix with the constants from the equations, then:
[tex]\[ x = \frac{|A_x|}{|A|} \][/tex]
[tex]\[ y = \frac{|A_y|}{|A|} \][/tex]
5. Calculate [tex]\(x\)[/tex]:
[tex]\[ x = \frac{|A_x|}{|A|} = \frac{80}{40} = 2.0 \][/tex]
6. Calculate [tex]\(y\)[/tex]:
[tex]\[ y = \frac{|A_y|}{|A|} = \frac{-200}{40} = -5.0 \][/tex]
So, the solution to the system of equations is [tex]\(x = 2\)[/tex] and [tex]\(y = -5\)[/tex]. Therefore, the correct answer is [tex]\(\boxed{x=2, y=-5}\)[/tex].
Thanks for using our service. We're always here to provide accurate and up-to-date answers to all your queries. We appreciate your time. Please come back anytime for the latest information and answers to your questions. We're glad you visited Westonci.ca. Return anytime for updated answers from our knowledgeable team.