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If |(2,5),(8,x^2)|=|(6,5),(8,3)| then fi...

If `|(2,5),(8,x^2)|=|(6,5),(8,3)|` then find the value of x .

A

`+- 2`

B

`+- 3`

C

0

D

`-1`

Text Solution

AI Generated Solution

The correct Answer is:
To solve the equation \( |(2,5),(8,x^2)| = |(6,5),(8,3)| \), we will calculate the determinants of both matrices and set them equal to each other. ### Step 1: Calculate the determinant of the left matrix The determinant of a 2x2 matrix \( |(a,b),(c,d)| \) is given by the formula: \[ |A| = ad - bc \] For the left matrix \( |(2,5),(8,x^2)| \): - \( a = 2 \) - \( b = 5 \) - \( c = 8 \) - \( d = x^2 \) So, the determinant is: \[ |L| = 2 \cdot x^2 - 5 \cdot 8 = 2x^2 - 40 \] ### Step 2: Calculate the determinant of the right matrix For the right matrix \( |(6,5),(8,3)| \): - \( a = 6 \) - \( b = 5 \) - \( c = 8 \) - \( d = 3 \) So, the determinant is: \[ |R| = 6 \cdot 3 - 5 \cdot 8 = 18 - 40 = -22 \] ### Step 3: Set the determinants equal to each other Now we set the determinants equal: \[ 2x^2 - 40 = -22 \] ### Step 4: Solve for \( x^2 \) Add 40 to both sides: \[ 2x^2 = -22 + 40 \] \[ 2x^2 = 18 \] Now, divide both sides by 2: \[ x^2 = 9 \] ### Step 5: Find the value of \( x \) Taking the square root of both sides gives: \[ x = \pm 3 \] Thus, the values of \( x \) are \( 3 \) and \( -3 \). ### Final Answer: The value of \( x \) is \( 3 \) or \( -3 \). ---
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