KnowledgeBoat Logo

Mathematics

If [8008][xy]=[2424]\begin{bmatrix}[r] 8 & 0 \ 0 & 8 \end{bmatrix}\begin{bmatrix}[r] x \ y \end{bmatrix} = \begin{bmatrix}[r] 24 \ -24 \end{bmatrix} then the values of x and y are :

  1. x = 3, y = -3

  2. x = 48, y = 0

  3. x = 0, y = 48

  4. x = 16, y = -32

Matrices

2 Likes

Answer

Given,

[8008][xy]=[2424][8×x+0×y0×x+8×y]=[2424][8x8y]=[2424][xy]=18[2424][xy]=[33].\Rightarrow \begin{bmatrix}[r] 8 & 0 \ 0 & 8 \end{bmatrix}\begin{bmatrix}[r] x \ y \end{bmatrix} = \begin{bmatrix}[r] 24 \ -24 \end{bmatrix} \\[1em] \Rightarrow \begin{bmatrix}[r] 8 \times x + 0 \times y \ 0 \times x + 8 \times y \end{bmatrix} = \begin{bmatrix}[r] 24 \ -24 \end{bmatrix} \\[1em] \Rightarrow \begin{bmatrix}[r] 8x \ 8y \end{bmatrix} = \begin{bmatrix}[r] 24 \ -24 \end{bmatrix} \\[1em] \Rightarrow \begin{bmatrix}[r] x \ y \end{bmatrix} = \dfrac{1}{8}\begin{bmatrix}[r] 24 \ -24 \end{bmatrix} \\[1em] \Rightarrow \begin{bmatrix}[r] x \ y \end{bmatrix} = \begin{bmatrix}[r] 3 \ -3 \end{bmatrix}.

∴ x =3, y = -3.

Hence, Option 1 is the correct option.

Answered By

2 Likes


Related Questions