Question

How do you solve the system of equations `6= 2x + 3y` and `- 2x - 6y = - 18`?

Answer 1

(-3, 4)
`x = -3 , y = 4`

Explanation:

Just add two equations, `2x` and `-2x` will cancel out each other.

`(2x+3y)+(-2x -6y) = 6 + (-18)`

simplify:

`-3y = -12`

so:

`y = \frac{-12}{-3} = 4`

put `y` in the first equation, you will get the value `x`

`6 = 2x + 3\times4 = 2x + 12`
`6 - 12= 2x`
`-6 = 2x`
`x = -3`

Or you can graph given equations, the answer will be the intersection of two lines.
graph{(2x+3y-6)(-2x-6y+18)=0 [-10, 10, -5, 5]}