Question

(i) 15x - 14y = 117
14x - 15y = 115​

Answer 1

SOLUTION:-

Given

• 15x-14x=117

• 14x-15y=115

To find

• Value of x and y

Explanation

We Solve the equations by

Elimination Method☆~⤵️

• 15x-14y= 117______________(1)

• 14x-15y=115_______________(2)

On adding eq 1 and 2

15x-14y=117

14x-15y= 115

____________

29x- 29y= 232

29(x-y)= 232

x-y= 232/29

x-y= 8______________(3)

On subtracting eq 2 from 1

15x-14y=117

14x-15y=115

- + -

___________

1x+1y= 2

1(x+y)=2

x+y=2/1

x+y=2___________________(4)

On subtracting eq 4 from 3

x-y= 8

x+y= 2

________

2x= 10

x= 10/2

x= 5

Putting x=5 in eq 4

x+y=2

5+y=2

y=2-5

y= -3

Hence

• X= 5

• y= -3

______________________________

Answer 2

Answer:

x =5

y=-3

In these type of questions where the coefficients of x and y are interchanged we usually first add and then subtract the equation.

Here it goes

15x - 14y =117

14x- 15y = 115

____________

29x - 29y= 232

x -y = 8

____________

Nad now subtracting them we get

15x -14y =117

14x - 15y=115

- + -

__________

x+y=2

__________

Now eleminating them we get

x - y =8

x+ y = 2

x=5

y= -3