Question

. Solve the following pair of linear equations for x: y -4x= 16 x- 5y= 9

Answer 1

Answer:

-89 /19

Step-by-step explanation:

Equation 1 => y - 4x = 16

Equation 2 => x - 5y = 9

In Equation 1, when we transpose [- 4x] to the R.H.S., we get:

y = 16 + 4x       ----Equation 3

On putting the value of y as 16 + 4x in Equation 2, we get:

x - 5 [16 + 4x] = 9

=> x - 80 - 20x = 9

=> [-19x] = 89

=> x = [-89 /19]

Hope it helps...

Thanks

Answer 2

y -4x = 16

-4x + y =16..........(1)

and,

x -5y = 9...........(2)

Now,

Multiplying eqn (1) by 5, we get

-20x +5y = 80..........(3)

Adding eqn (2) and (3), we get

1x - 5y = 9

-20x +5y = 80

___________

-19x = 89

x= 89/19

x=4.684

put the value of x in eqn (1),

-4(4.684) + y = 16

-18.736 + y = 16

y = 16/-18.736

y = -0.853

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