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If \(\begin{bmatrix}2x+y &3y \\[0.3em]0 & 4 \\[0.3em]\end{bmatrix}\)= \(\begin{bmatrix}6&0 \\[0.3em]6 & 4 \\[0.3em]\end{bmatrix}\), then find x. |
Answer» We are given that, \(\begin{bmatrix}2x+y &3y \\[0.3em]0 & 4 \\[0.3em]\end{bmatrix}\)= \(\begin{bmatrix}6&0 \\[0.3em]6 & 4 \\[0.3em]\end{bmatrix}\) We need to find the value of x. We know by the property of matrices, \(\begin{bmatrix} a_{11}& a_{12} \\[0.3em] a_{21} & a_{22} \\[0.3em] \end{bmatrix}\)= \(\begin{bmatrix} b_{11}& b_{12} \\[0.3em] b_{21} & b_{22} \\[0.3em] \end{bmatrix}\) This implies, a11 = b11, a12 = b12, a21 = b21 and a22 = b22 So, if we have \(\begin{bmatrix}2x+y &3y \\[0.3em]0 & 4 \\[0.3em]\end{bmatrix}\)= \(\begin{bmatrix}6&0 \\[0.3em]6 & 4 \\[0.3em]\end{bmatrix}\) Corresponding elements of two elements are equal. That is, 2x + y = 6 …(i) 3y = 0 …(ii) To solve for x, We have equations (i) and (ii). We can’t solve for x using only equation (i) as equation (i) contains x as well as y. We need to find the value of y from equation (ii) first. From equation (ii), 3y = 0 ⇒ y = \(\frac{0}{3}\) ⇒ y = 0 Substituting y = 0 in equation (i), 2x + y = 6 ⇒ 2x + (0) = 6 ⇒ 2x = 6 – 0 ⇒ 2x = 6 ⇒ x = \(\frac{6}{2}\) ⇒ x = 3 Thus, we get x = 3. |
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