Question

If 3x+2y=8;2x+3y=7then findx+y&x-y

Answer 1

Given:

• 3x + 2y = 8
• 2x + 3y = 7

To find:

1. x + y = ?
2. x - y = ?

Method:

Adding the 2 given equations;

                 3x + 2y = 8

        (+)     2x + 3y = 7  

                 5x + 5y = 15

⇒ 5(x + y) = 15

⇒ x + y = 15 ÷ 5

⇒ x + y = 3

Now subtracting the 2 equations,

                 3x + 2y = 8

        (-)      2x + 3y = 7  

                  x - y = 1

⇒ x - y = 1

Therefore,

x + y = 3

x - y = 1

Answer 2

Solution

Given ,

• 3x + 2y = 8
• 2x + 3y = 7

To find ,

• X + y = ?
• X - y = ?

So Now ,

By adding the two given equation we get ;

3x + 2y = 8

(+) 2x + 3y = 7

____________

5x + 5y = 15

Now , solving this equation we get ;

=> 5x + 5y = 15

=> 5(X+y) = 15

=> X + y = 15/5

=> X +y = 3

So , we get the value of X+y =3

Now ,

by subtracting now the two equation we get ;

3x + 2y = 8

(-) 2x + 3y = 7

___________

X - y = 1

So, we get the value of x-y = 1

• Hence , X +y = 3
• X - y = 1