Answer :

[tex]5x+y=-10\\ \\ 7x-3y=-36[/tex]

Let's multiply the first equation by 3. (As you can see y's coefficient in the first one is 1 and in the second one is -3 , we will multiply the first equation by 3 so when we add the equations their sum will be 0)

[tex]3\cdot (5x+y)=3\cdot -10\\ \\ 15x+3y=-30[/tex]

Now let's add this new equation and our second equation.

[tex]7x-3y=-36\\ \\ 15x+3y=-30\\ \\ (15x+3y)+(7x-3y)=(-30)+(-36)\\ \\ 15x+7x+3y-3y=-30-36\\ \\ 22x=-66\\ \\ x=\frac { -66 }{ 22 } \\ \\ x=-3[/tex]

We found x=-3

Now let's plug x's value in one of the equations to find y's value.

[tex]x=-3\\ \\ 5x+y=-10\\ \\ 5\cdot -3+y=-10\\ \\ -15+y=-10\\ \\ y=-10+15\\ \\ y=5[/tex]

So we found y=5

Solution ;

(-3, 5)

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