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If [(3,-2),(-1//6,4)][(2x),(1)] +2 [(-4)...

If `[(3,-2),(-1//6,4)][(2x),(1)] +2 [(-4),(5)]=4[(2),(y)]` then find the values of x and y .

A

`13/4,1`

B

0,3

C

`3 , 13/4`

D

3,0

Text Solution

AI Generated Solution

The correct Answer is:
To solve the equation given in the question, we will break it down step by step. ### Given Equation: \[ \begin{pmatrix} 3 & -2 \\ -\frac{1}{6} & 4 \end{pmatrix} \begin{pmatrix} 2x \\ 1 \end{pmatrix} + 2 \begin{pmatrix} -4 \\ 5 \end{pmatrix} = 4 \begin{pmatrix} 2 \\ y \end{pmatrix} \] ### Step 1: Multiply the first matrix with the vector We will first calculate the product of the matrix and the vector: \[ \begin{pmatrix} 3 & -2 \\ -\frac{1}{6} & 4 \end{pmatrix} \begin{pmatrix} 2x \\ 1 \end{pmatrix} \] Calculating the first row: \[ 3(2x) + (-2)(1) = 6x - 2 \] Calculating the second row: \[ -\frac{1}{6}(2x) + 4(1) = -\frac{2x}{6} + 4 = -\frac{x}{3} + 4 \] So, we have: \[ \begin{pmatrix} 6x - 2 \\ -\frac{x}{3} + 4 \end{pmatrix} \] ### Step 2: Add the second matrix Now we will add \(2 \begin{pmatrix} -4 \\ 5 \end{pmatrix}\) to the result: \[ 2 \begin{pmatrix} -4 \\ 5 \end{pmatrix} = \begin{pmatrix} -8 \\ 10 \end{pmatrix} \] Adding the two matrices: \[ \begin{pmatrix} 6x - 2 \\ -\frac{x}{3} + 4 \end{pmatrix} + \begin{pmatrix} -8 \\ 10 \end{pmatrix} = \begin{pmatrix} 6x - 2 - 8 \\ -\frac{x}{3} + 4 + 10 \end{pmatrix} \] \[ = \begin{pmatrix} 6x - 10 \\ -\frac{x}{3} + 14 \end{pmatrix} \] ### Step 3: Multiply the right side Now, let's calculate the right side: \[ 4 \begin{pmatrix} 2 \\ y \end{pmatrix} = \begin{pmatrix} 8 \\ 4y \end{pmatrix} \] ### Step 4: Set the two sides equal Now we set the left-hand side equal to the right-hand side: \[ \begin{pmatrix} 6x - 10 \\ -\frac{x}{3} + 14 \end{pmatrix} = \begin{pmatrix} 8 \\ 4y \end{pmatrix} \] ### Step 5: Create equations from the matrix equality From the first row: \[ 6x - 10 = 8 \] From the second row: \[ -\frac{x}{3} + 14 = 4y \] ### Step 6: Solve for x From the first equation: \[ 6x - 10 = 8 \implies 6x = 18 \implies x = 3 \] ### Step 7: Substitute x into the second equation Now substitute \(x = 3\) into the second equation: \[ -\frac{3}{3} + 14 = 4y \implies -1 + 14 = 4y \implies 13 = 4y \implies y = \frac{13}{4} \] ### Final Values Thus, the values of \(x\) and \(y\) are: \[ x = 3, \quad y = \frac{13}{4} \]
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