Question
Solve system of linear equations, using matrix method.
4x - 3y = 3
3x - 5y = 7

Answer

Matrix form of given equations AX = B $\Rightarrow\ \begin{bmatrix}4&-3\\3&-5\end{bmatrix}\begin{bmatrix}x\\y\end{bmatrix}=\begin{bmatrix}3\\7\end{bmatrix}$ $\text{Here}\ \text{A}=\begin{bmatrix}4&-3\\3&-5\end{bmatrix},\ \text{X}=\begin{bmatrix}x\\y\end{bmatrix}\text{and B}=\begin{bmatrix}3\\7\end{bmatrix}$ $\therefore\ \text{|A|}=\begin{vmatrix}4&-3\\3&-5\end{vmatrix}=-20-(-9)=-20+9=-11\neq0$ Therefore, solution is unique and $\text{X=A}^{-1}\text{B}=\frac{1}{\text{|A|}}\text{(adj. A)B}$ $\Rightarrow\ \begin{bmatrix}x\\y\end{bmatrix}=\frac{1}{-11}\begin{bmatrix}-5&3\\-3&4\end{bmatrix}\begin{bmatrix}3\\7\end{bmatrix}$ $=\frac{1}{-11}\begin{bmatrix}-15+21\\-9+28\end{bmatrix}=\frac{1}{-11}\begin{bmatrix}6\\19\end{bmatrix}=\begin{bmatrix}\frac{-6}{11}\\\frac{-19}{11}\end{bmatrix}$ Therefore, $x=\frac{-6}{11}\text{and}\ y=\frac{-19}{11}$

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

Let $L$ be the set of all lines in $xy$ plane and $R$ be the relation in $L$ define as $R = \{(L_1, L_2) : L_1 || L_2\}.$ Show that $R$ is an equivalence relation. Find the set of all lines related to the line $y = 2x + 4.$
Evaluate the following integrals:$\int\text{e}^{\text{}x}\Big(\frac{1+\sin\text{x}}{1+\cos\text{x}}\Big)\text{dx}$
Find the vector equation of the line passing through (1, 2, 3) and perpendicular to the plane $\vec{\text{r}}.\Big(\hat{\text{i}}+2\hat{\text{j}}-5\hat{\text{k}}\Big)+9=0.$
If a leap year is selected at random, what is the chance that it will contain 53 tuesdays?
Three events A, B and C have probabilities $\frac{2}{5},\frac{1}{3}$ and $\frac{1}{2},$ respectively. Given than $\text{P}(\text{A}\cap\text{C})=\frac{1}{5}$ and $\text{P}(\text{B}\cap\text{C})=\frac{1}{4},$ find the values of $\text{P}\Big(\frac{\text{C}}{\text{B}}\Big)$ and $\text{P}(\text{A}'\cap\text{C}').$
Evaluate the following:
$\int\frac{\text{dx}}{\text{x}\sqrt{\text{x}^4}-1}$
Hint: Put $\text{x}^2=\sec\theta$
By using the properties of definite integral, evaluate the integral in Exercise:
$\int^{\frac{\pi}{2}}_{0}\frac{\sqrt{\sin\text{x}}}{\sqrt{\sin\text{x}}+\sqrt{\cos\text{x}}}\text{dx}$
Show that $f(x) = e^{2x}$ is increasing on $R.$
Represent the following families of curves by forming the corresponding differential equation:
$\text{y}^2=4\text{a}(\text{x}-\text{b})$
In roulette, Figure, the wheel has 13 numbers 0, 1, 2,...., 12 maked on equally spaced slots. A player sets Rs 10 on a given number. He recieves Rs 100 from the organiser of the game if the ball comes to rest in this slot; otherwise he gets nothing. If X denotes the players net gain/loss, Find E(X).