Question

5x+7y=17 ; 3x-2y=4 By equating coefficients of variables, solve the equation.

Answer 1

5x + 7y = 17

=> 10x + 14y = 34 -------(1)

3x - 2y = 4

=> 21x - 14y = 28 -----(2)

On adding equation 1 and 2, we get

31x = 62

=> x = 2

Now,

On substituting the value of x in equation (1), we get

10(2) + 14y = 34

=> 20 + 14y = 34

=> 14y = 14

=> y = 1

Answer 2

Solution :

Given simultaneous equations are ,

5x + 7y = 17

multiply both sides with 2 , we get

10x + 14y = 34 ---( 1 )

3x - 2y = 4

multiply both sides with 7 , we get

21x - 14y = 28 ---( 2 )

Add ( 1 ) & ( 2 ) , we get

31x = 62

=> x = 62/31

=> x = 2

substitute x = 2 in equation ( 1 ) ,

10 × 2 + 14y = 34

=> 20 + 14y = 34

=> 14y = 34 - 20

=> 14y = 14

=> y = 14/14

y = 1

Therefore ,

x = 2 , y = 1

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