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Find matrices 'X' and 'Y' if : 2X+3Y=[...

Find matrices 'X' and 'Y' if :
`2X+3Y=[(2,3),(4,0)]` and `3X+2Y=[(2,-2),(-1,5)]`

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To find the matrices \( X \) and \( Y \) given the equations: 1. \( 2X + 3Y = \begin{pmatrix} 2 & 3 \\ 4 & 0 \end{pmatrix} \) (Equation 1) 2. \( 3X + 2Y = \begin{pmatrix} 2 & -2 \\ -1 & 5 \end{pmatrix} \) (Equation 2) We will solve these equations step by step. ### Step 1: Multiply the equations to eliminate one variable Let's multiply Equation 1 by 3 and Equation 2 by 2 to make the coefficients of \( X \) the same. \[ 3(2X + 3Y) = 3\begin{pmatrix} 2 & 3 \\ 4 & 0 \end{pmatrix} \implies 6X + 9Y = \begin{pmatrix} 6 & 9 \\ 12 & 0 \end{pmatrix} \] \[ 2(3X + 2Y) = 2\begin{pmatrix} 2 & -2 \\ -1 & 5 \end{pmatrix} \implies 6X + 4Y = \begin{pmatrix} 4 & -4 \\ -2 & 10 \end{pmatrix} \] ### Step 2: Subtract the two equations Now we will subtract the second modified equation from the first modified equation: \[ (6X + 9Y) - (6X + 4Y) = \begin{pmatrix} 6 & 9 \\ 12 & 0 \end{pmatrix} - \begin{pmatrix} 4 & -4 \\ -2 & 10 \end{pmatrix} \] This simplifies to: \[ 5Y = \begin{pmatrix} 6 - 4 & 9 + 4 \\ 12 + 2 & 0 - 10 \end{pmatrix} = \begin{pmatrix} 2 & 13 \\ 14 & -10 \end{pmatrix} \] ### Step 3: Solve for \( Y \) Now, we can solve for \( Y \) by dividing both sides by 5: \[ Y = \frac{1}{5} \begin{pmatrix} 2 & 13 \\ 14 & -10 \end{pmatrix} = \begin{pmatrix} \frac{2}{5} & \frac{13}{5} \\ \frac{14}{5} & -2 \end{pmatrix} \] ### Step 4: Substitute \( Y \) back to find \( X \) Now we substitute \( Y \) back into Equation 1 to find \( X \): \[ 2X + 3\begin{pmatrix} \frac{2}{5} & \frac{13}{5} \\ \frac{14}{5} & -2 \end{pmatrix} = \begin{pmatrix} 2 & 3 \\ 4 & 0 \end{pmatrix} \] Calculating \( 3Y \): \[ 3Y = \begin{pmatrix} \frac{6}{5} & \frac{39}{5} \\ \frac{42}{5} & -6 \end{pmatrix} \] Now we substitute: \[ 2X + \begin{pmatrix} \frac{6}{5} & \frac{39}{5} \\ \frac{42}{5} & -6 \end{pmatrix} = \begin{pmatrix} 2 & 3 \\ 4 & 0 \end{pmatrix} \] ### Step 5: Solve for \( 2X \) Subtract \( 3Y \) from both sides: \[ 2X = \begin{pmatrix} 2 & 3 \\ 4 & 0 \end{pmatrix} - \begin{pmatrix} \frac{6}{5} & \frac{39}{5} \\ \frac{42}{5} & -6 \end{pmatrix} \] Calculating the right side: \[ = \begin{pmatrix} 2 - \frac{6}{5} & 3 - \frac{39}{5} \\ 4 - \frac{42}{5} & 0 + 6 \end{pmatrix} = \begin{pmatrix} \frac{10}{5} - \frac{6}{5} & \frac{15}{5} - \frac{39}{5} \\ \frac{20}{5} - \frac{42}{5} & 6 \end{pmatrix} \] This simplifies to: \[ = \begin{pmatrix} \frac{4}{5} & -\frac{24}{5} \\ -\frac{22}{5} & 6 \end{pmatrix} \] ### Step 6: Solve for \( X \) Now divide by 2: \[ X = \frac{1}{2} \begin{pmatrix} \frac{4}{5} & -\frac{24}{5} \\ -\frac{22}{5} & 6 \end{pmatrix} = \begin{pmatrix} \frac{2}{5} & -\frac{12}{5} \\ -\frac{11}{5} & 3 \end{pmatrix} \] ### Final Answer Thus, the matrices \( X \) and \( Y \) are: \[ X = \begin{pmatrix} \frac{2}{5} & -\frac{12}{5} \\ -\frac{11}{5} & 3 \end{pmatrix}, \quad Y = \begin{pmatrix} \frac{2}{5} & \frac{13}{5} \\ \frac{14}{5} & -2 \end{pmatrix} \]
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