Question

8.The solution of the following pair of simultaneous equation is: 9x-4y=-14,4x-9y=1 ​

Answer 1

Answer:

9x-4y = -14 (1)

4x-9y = 1. (2)

Adding equation (1) & (2)

9x-4y =-14

+

4x-9y =. 1

=

13x - 13y = -13

13x - 13y = -1313 (x-y) = -13

Dividing eqn by 13.

:. x-y = -1. (3)

Subtracting equation (1) from (2)

9x -4y = - 14

-

4x - 9y =. 1

-. +. -

=

5x + 5y = -15

Dividing eqn by 5

Dividing eqn by 5:. x + y = -3. (4)

Adding eqn (3) & (4)

x - y = -1

x + y = -3

= 2x = -4

x = -2

substituting x= - 2 in eqn

9x-4y= -14

9× -2 - 4y = -14

-18 -4y = -14

-4y = -14 +18.

-4y = 4

y = -1