Question

Find the value of (x + y ) , if 3x + 4y =11 ;4x + 3y = 10

Answer 1

Answer:

Value of x = 1 and value of y = 2

∴ (x + y) = 3

Explanation:

3x + 4y =11

4x + 3y = 10

Making value of x equal, so,

3x + 4y =11     x4

4x + 3y = 10   x3

⇒ 12x + 16y = 44    -  (i)

   12x + 9y = 30     -  (ii)

    Subtracting the above values from (ii) to (i)...

   Value got: 7y = 14

                  ⇒ y = 14 / 7

                     ∴ y = 2

Applying y=2 in equation (i)

⇒ 3x + 4 * 2 = 11

⇒ 3x + 8 = 11

⇒ 3x = 11 - 8

⇒ 3x = 3

⇒ x = 3 / 3

                     ∴ x = 1

Answer 2

This answer is for one mark question.