Question

VERY URGENT!!!
solve by cross multiplication method (5/x+y)-(2/x-y)=-1 and (15/x+y)+(7/x-y)=10

Answer 1

Answer:

The value of x and y is 3 and 2 for the equation solved by cross multiplication method.

Step-by-step explanation:

Solving the value of x and y using cross multiplication method for that first,

Let us assume that $x+y=\frac{1}{a} \text { and } x-y=\frac{1}{b}$

Therefore putting the value of a and b in $\frac{5}{x+y}-\frac{2}{x-y}=-1 \text { and } \frac{15}{x+y}+\frac{7}{x-y}=10$ we get

5a-2b=-1 ,15a+7b=10

Solving the equation in,

$\begin{array}{l}{5 a-2 b=-1} \\ {15 a+7 b=10}\end{array}$

After solving the equation in cross multiplication method we get,  

$\begin{array}{l}{(5 a-2 b=-1)} \\ {(15 a+7 b=10)}\end{array}$$\begin{array}{cccc}{b} & {c} & {a} & {b} \\ {-2} & {=1} & {=5} & {=-2} \\ {7} & {-10} & {15} & {7}\end{array}$

After solving the equation be  

$\begin{array}{l}{\frac{a}{20-7}=\frac{b}{15+50}=\frac{1}{35+30}} \\ {\frac{a}{14}=\frac{b}{65}=\frac{1}{65}} \\ {a=\frac{1}{5}, b=1}\end{array}$

Putting the value of a and b = x+y=1/a  and x-y=1/b

x+y=5 and x-y=1

After solving we get y = 2 and x = 3

Hence the value of x and y is 3 and 2

Answer 2

Answer:

Solving the value of x and y using cross multiplication method for that first,

Let us assume that  

Therefore putting the value of a and b in  we get

5a-2b=-1 ,15a+7b=10

Solving the equation in,

After solving the equation in cross multiplication method we get,  

After solving the equation be  

Putting the value of a and b = x+y=1/a  and x-y=1/b

x+y=5 and x-y=1

After solving we get y = 2 and x = 3

Hence the value of x and y is 3 and 2

Step-by-step explanation: