Can someone please explain how to solve the attached question? Solve the system of equations: `3+2x-y=0` `-3-7y=10x`

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Solve the following system of two equations with two unknowns:

`3+2x-y=0`           (1)

`-3-7y=10x`         (2)

Write each equation in standard form `(ax+by=c)`.

Subtract 3 to each side of (1).

`2x-y=-3`               (3)

Add 3 to each side of (2).

`-7y=10x+3`         (2.1)

Subtract 10x to each side of (2.1)

`-10x-7y=3`           (4)

Multiply (3) by (5) and add to (4) to solve by elimination.

`10x-5y=-15`         (5)

`-10x-7y=3`

---------------------

         `-12y=-12`    (6)

Divide (6) by -12 to obtain the value of y.

`y=1`

Substitute y=1 in (3)

`2x-1=-3`

Solve for x:

`2x=-3+1`

`x=-2/2=-1`

Therefore x=-1 and y=1.

Verify by substituting x=-1 and y=1 in (2)

-3-(7)(1)=10(-1)

-3-7=-10

-10=-10

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