MCQ
If $\left[\begin{array}{cc}2 x+y & 4 x \\ 5 x-7 & 4 x\end{array}\right]=\left[\begin{array}{cc}7 & 7 y-13 \\ y & x+6\end{array}\right]$, then the values of $x, y$ respectively are
  • A
    3,1
  • 2,3
  • C
    2,4
  • D
    3,3

Answer

Correct option: B.
2,3
(b) : $\left[\begin{array}{cc}2 x+y & 4 x \\ 5 x-7 & 4 x\end{array}\right]=\left[\begin{array}{cc}7 & 7 y-13 \\ y & x+6\end{array}\right]$
On comparing, we get
$
4 x=x+6 \Rightarrow x=2 \text { and } 2 x+y=7 \Rightarrow y=7-4=3
$

Need a full question paper?

Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.

Start Generating Free

Similar questions

If $x = x ( y )$ is the solution of the differential equation $y \frac{d x}{d y}=2 x+y^{3}(y+1) e^{y}, x(1)=0$; then $x(e)$ is equal to
The integral $\int {\sqrt {1 + 2\cot \,x\,\left( {\cos ec\,x + \cot \,x} \right)} \,dx} $ $\left( {0 < x < \frac{\pi }{2}} \right)$ is equal to ( where $C$ is a constant of integration)
If $\text{A}=\displaystyle \begin{vmatrix} 1 &\text{amp; } 0 \\ 1 &\text{amp; } 0 \end{vmatrix}$ And $\text{B}=\displaystyle \begin{vmatrix} 1 &\text{amp; } 0 \\ 0 &\text{amp; } 1 \end{vmatrix}$ then $\text{A+B}=$
  1. $\text{A}$
  2. $\text{B}$
  3. $\displaystyle \begin{vmatrix}2&0 \\ 1 &1 \end{vmatrix}$
  4. $\displaystyle \begin{vmatrix}0&2 \\ 2 &2 \end{vmatrix}$
If $(\text{x}+\text{y})^2\frac{\text{dy}}{\text{dx}}=\text{a}^2,\text{y}=0$ when x = 0, then y = a if $\frac{\text{x}}{\text{a}}=$
  1. $1$
  2. $\tan1$
  3. $\tan1+1$
  4. $\tan1-1$
The solution of the equation $\frac{d y}{d x}=e^{x-y}$ is :
$\int_{}^{} {\sin (\log x)dx = } $
The solution of the differential equartion $\frac{\text{dy}}{\text{dx}}-\frac{\text{y}(\text{x}+1)}{\text{x}}=0$ is given by:
  1. $\text{y}=\text{xe}^{\text{x}+\text{C}}$
  2. $\text{x}=\text{ye}^{\text{x}}$
  3. $\text{y}=\text{x}+\text{c}$
  4. $\text{xy}=\text{e}^{\text{x}}+\text{C}$ 
If $0 < x < \frac{1}{\sqrt{2}}$ and $\frac{\sin ^{-1} x}{\alpha}=\frac{\cos ^{-1} x}{\beta}$, then a value of $\sin \left(\frac{2 \pi \alpha}{\alpha+\beta}\right)$ is$......$
If the value of the integral $\int_{-\frac{\pi}{2}}^{\frac{\pi}{2}}\left(\frac{x^2 \cos x}{1+\pi^x}+\frac{1+\sin ^2 x}{1+e^{\sin x^{323}}}\right) d x=\frac{\pi}{4}(\pi+a)-2$, then the value of $a$ is
Let $f\left( x \right) = {\sin ^4}\,x + {\cos ^4}\,x$. Then $f$ is an increasing function in the interval