Question

Solve the pair of equations Hence , find the value of 5x - 3y
2/x + 3/y =11
5/x - 4/y =-7

Answer 1

The value of 5x-3y is 4

Step-by-step explanation:

Given equations are $\frac{2}{x}+\frac{3}{y}=11\hfill (1)$ and  

$\frac{5}{x}-\frac{4}{y}=-7\hfill (2)$

To find the value of 5x-3y :

First find the values of x and y :

• Equation (1) becomes $\frac{2}{x}+\frac{3}{y}=11\hfill (1)$
• $2y+3x=11xy\hfill (3)$
• Equation (2) becomes $\frac{5}{x}-\frac{4}{y}=-7\hfill (2)$
• $5y-4x=-7xy\hfill (4)$

Now solving the equations (3) and (4) by Elimination method  

• Multiply the equation (3) into 4 we get
• $8y+12x=44xy\hfill (5)$
• Multiply the equation (4) into 3 we get
• $15y-12x=-21xy\hfill (6)$

Now adding the equations (5) and (6) we get

$8y+12x=44xy$

$15y-12x=-21xy$

___________________

$23y=23xy$

• Rewritting the equation  
• $23xy=23y$
• $x=\frac{23y}{23y}$
• $=1$

Therefore $x=1$

Substitute the value of x in the equation (3) we get

• $2y+3(1)=11(1)y$
• $2y+3=11y$
• $2y-11y=-3$
• $-9y=-3$
• $y=\frac{3}{9}$

Therefore $y=\frac{1}{3}$

Now to find 5x-3y

Substitute the values of x and y we get

• $5(1)-3(\frac{1}{3})=5-1$
• $=4$

Therefore the value of 5x-3y=4

Answer 2

Answer:

The required value is 4.

Step-by-step explanation:

Since we have given that

Let,

So, it becomes,

So, we get that

So, it becomes,

Hence, the required value is 4.

# learn more:

Solve the pair of equations :

2/x + 3/y = 11 , 5/x - 4/y = -7

Hence, find the value of 5x - 3y.​