Home
Class 12
MATHS
Solve the following equations using inv...

Solve the following equations using inverse of a matrix.
`{:(5x+2y=3),(3x+2y=5):}`

Text Solution

AI Generated Solution

The correct Answer is:
To solve the system of equations using the inverse of a matrix, we will follow these steps: ### Step 1: Write the equations in matrix form We have the equations: 1. \( 5x + 2y = 3 \) 2. \( 3x + 2y = 5 \) We can express this in matrix form as: \[ A \cdot X = B \] where \[ A = \begin{pmatrix} 5 & 2 \\ 3 & 2 \end{pmatrix}, \quad X = \begin{pmatrix} x \\ y \end{pmatrix}, \quad B = \begin{pmatrix} 3 \\ 5 \end{pmatrix} \] ### Step 2: Find the inverse of matrix A To find the inverse of matrix \( A \), we need to calculate the determinant of \( A \): \[ \text{det}(A) = (5)(2) - (2)(3) = 10 - 6 = 4 \] Since the determinant is not zero, the inverse exists. The formula for the inverse of a 2x2 matrix \( A = \begin{pmatrix} a & b \\ c & d \end{pmatrix} \) is given by: \[ A^{-1} = \frac{1}{\text{det}(A)} \begin{pmatrix} d & -b \\ -c & a \end{pmatrix} \] Applying this to our matrix \( A \): \[ A^{-1} = \frac{1}{4} \begin{pmatrix} 2 & -2 \\ -3 & 5 \end{pmatrix} = \begin{pmatrix} \frac{1}{2} & -\frac{1}{2} \\ -\frac{3}{4} & \frac{5}{4} \end{pmatrix} \] ### Step 3: Multiply the inverse of A by B Now, we will find \( X \) by multiplying \( A^{-1} \) with \( B \): \[ X = A^{-1}B = \begin{pmatrix} \frac{1}{2} & -\frac{1}{2} \\ -\frac{3}{4} & \frac{5}{4} \end{pmatrix} \begin{pmatrix} 3 \\ 5 \end{pmatrix} \] Calculating the multiplication: 1. For \( x \): \[ x = \frac{1}{2} \cdot 3 + \left(-\frac{1}{2}\right) \cdot 5 = \frac{3}{2} - \frac{5}{2} = -1 \] 2. For \( y \): \[ y = -\frac{3}{4} \cdot 3 + \frac{5}{4} \cdot 5 = -\frac{9}{4} + \frac{25}{4} = \frac{16}{4} = 4 \] Thus, we have: \[ X = \begin{pmatrix} -1 \\ 4 \end{pmatrix} \] ### Final Solution The solution to the system of equations is: \[ x = -1, \quad y = 4 \]
Promotional Banner

Topper's Solved these Questions

  • DETERMINANTS

    MODERN PUBLICATION|Exercise Exercise 4(h) (LONG ANSWER TYPE QUESTIONS)|52 Videos
  • DETERMINANTS

    MODERN PUBLICATION|Exercise OBJECTIVE TYPE QUESTIONS (Multiple choice question)|25 Videos
  • DETERMINANTS

    MODERN PUBLICATION|Exercise Exercise 4(g) (LONG ANSWER TYPE QUESTIONS)|15 Videos
  • CONTINUITY AND DIFFERENTIABILITY

    MODERN PUBLICATION|Exercise CHAPTER TEST|12 Videos
  • DIFFERENTIAL EQUATIONS

    MODERN PUBLICATION|Exercise CHAPTER TEST (9)|12 Videos

Similar Questions

Explore conceptually related problems

Solve the following equations using inverse of a matrix. {:(2x+5y=1),(3x+2y=7):}

Solve the following equations using inverse of a matrix. {:(2x-y=-2),(3x+4y=3):}

Solve the following equations, using inverse of a matrix : {:(5x-y+z=4),(3x+2y-5z=2),(x+3y-2z=5):}

Solve the following equations using inverse of a matrix. {:(2x+3y=4),(4x+5y=6):}

Solve the following equations, using inverse of a matrix : {:(x-2y+3z=-5),(3x+y+z=8),(2x-y+2z=1):}

Solve the following equations, using inverse of a matrix : {:(2x+3y+3z=5),(x-2y+z=4),(3x-y-2z=3):}

Solve the following equations, using inverse of a matrix : {:(3x-y+z=5),(2x-2y+3z=7),(x+y-z=-1):}

Solve the following equations, using inverse of a matrix : {:(3x-2y+3z=8),(2x+y-z=1),(4x-3y+2z=4):}

Solve the following equations, using inverse of a matrix : {:(x+2y=5),(y+2z=8),(z+2x=5):}

Solve the following equations, using inverse of a matrix : {:(8x+4y+3z=18),(2x+y+z=5),(x+2y+z=5):}