Question

3x-y=7 ; x+4y=11 solve the following equation.​

Answer 1

Answer:

x = 3, y = 2

Step-by-step explanation:

4(3x-y=7)

12x - 4y = 28 ------- 1

x + 4y = 11 -------------2

Eliminating eq 1 and 2

    12x - 4y = 28

 +    x    + 4y = 11                                                                                                                 --------------------------

 13x = 39

x = 3--------------------3

Substituting (x=3) in eq 2

x + 4y = 11

3 + 4y = 11

4y = 8

y = 2

Answer 2

Answer:

x =3

y=2

Step-by-step explanation:

solution------->

Given:-

$3x - y = 7......................(1) \\ \\ x + 4y = 11...................(2) \\ \\ now \: multiply \: equation \:( 1 )\: by \: 4 \\ \\ we \: get \\ \\ 12x - 4y = 28................(3) \\ \\ now \: add \:(2) \: and \: (3) \\ \\ we \: get \\ \\ \: \: x + 4y = 11 \\ + 12x - 4y = 28 \\ - - - - - - - - \\ 13x = 39 \\ x = \frac{39}{13} \\ x = 3 \\ \\ now \: put \: x = 3 \: in \: any \: equation \: \\ put \: in \: equation \: (1) \\ \\ 3x - y = 7 \\ 3 \times 3 - y = 7 \\ 9 - y = 7 \\ - y = 7 - 9 \\ - y = - 2 \\ \\ y = 2$