Question

solve by elimination method 7x-15y=2, x+2y=3​

Answer 1

Step-by-step explanation:

7x+15y=2 …… (eqn. 1)

x+2y=3………..(eqn. 2)

let's multiply eqn.2 by 7 to eliminate the x variable of eqn. 1

Eqn. 2 => 7x+14y=21

Now subtract eqn.2 from eqn.1

i.e. 7x+15y-(7x+14y)=2–21

7x+15y-7x-14y=-19

y=-19

Now substitute value of y in eqn. 2 we get

x+2(-19)=3

x-38=3

or x=3+38

or x=41

Ans. x=41, y=-19

Answer 2

Step-by-step explanation:

$\bold{\color{green}{2x + 3y = 8}}$

$\bold\purple{4x + 6y = 7}$

${\fbox{\red{Multiply \: by \: 4}}}$

$\bold\blue{4x + 6y = 16}$

${\fbox{LHS \: of \: i \: and \: ii \: are \: same \: but \: RHS\: is \: different}}$

${\fbox{\color{navy}{Hence \: the \: solution \: does \: not \: exist}}}$