Question

How do you solve 2x-5y=-19 and 3x+2y =0?

Answer 1

`y=3` and `x=-2`

Explanation:

There are multiple ways to solve simultaneous equations. You can use an "elimination" method, where you remove one of the unknown from the equation or use a "substitution" method. I will use a substitution method, where you substitute one variable with an expression containing the other value.

if

`3x+2y=0`

then

`y=((-3x)/2)`

Substitute this value for `y` into the other equation:

`2x-5y=-19`

`2x-5((-3x)/2)=-19`

`2x+(15x)/2=-19`

`4x+15x=-38`

`19x=-39`

`x=-2`

So, using any of the two equations we can find `y`:

`2(-2)-5y=-19`

`-4-5y=-19`

`-5y=-15`

`y=3`