Question

Solve by Elimination by equating Coefficients method and find 2x + y

$4. \: \: 4x + \frac{6}{y} = 15$

$6x - \frac{8}{y} = 14$

Ans: 3 , 2

Class 10

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Answer 1

$\bold{Answer :}$

The given equations are -

4x + 6/y = 15 ...(i)

6x - 8/y = 14 ...(ii)

Now, multiplying (i) by 6 and (ii) by 4, we get

24x + 36/y = 90

24x - 32/y = 56

On subtraction, we get

36/y - (- 32/y) = 90 - 56

or, 36/y + 32/y = 34

or, 68/y = 34

or, y = 68/34

or, y = 2

Putting y = 2 in (i), we get

4x + 6/2 = 15

or, 4x + 3 = 15

or, 4x = 15 - 3

or, 4x = 12

or, x = 12/4

or, x = 3

Therefore, the required solution be

x = 3 and y = 2

Now, 2x + y

= 2 (3) + 2

= 6 + 2

= 8

#$\bold{MarkAsBrainliest}$

Answer 2

Let the value of 1 / y be a.

Then,

4x + 6a = 15

6x - 8a = 14

Multiplying by 6, 6 ( 4x + 6a = 15)

=> 24x + 36a = 90 ---- ( i )

Multiplying by 4, 4 ( 6x - 8a = 14)

=> 24x - 32 a = 56 ---- ( ii )

Now, subtracting both equations,

24x + 36a = 90

- 24x + 32 a = -56

=> 68 a = 34

=> a = 34 / 68

=> a = 1 / 2

Putting value of 'a' in y,

1 / y = a

Y = 2

Putting value of a in equation (ii),

24x - 32 ( 1 /2) = 56

24x = 56 + 16

24x = 72

x = 72 / 24

x = 3

ANSWER =

X = 3
Y = 2.

2x + y = 2 ( 3) + 2

= 8