Question

How do you solve the following system: #-3x + y = -4, 4x + 2y = 0 #?

Answer 1

`x=4/5` and `y=-8/5`

Explanation:

we begin with `-3x+y=-4` and `4x+2y=0`

Now, I'm going to solve for `y` in `-3x+y=-4` which looks like `y=-4+3x`.

So no we can replace the `y` in the second equation with `-4+3x`.

That gives us `4x+2(-4+3x)=0` which we can simplify to `4x-8+6x=0`. This becomes `10x=8` or `x=4/5`.

No, we can solve for `y`.

`y=-4+3(4/5)`, which is `-4+12/5` or `-8/5`.

Now we should double check our math. If we did this right then `4(4/5)+2(-8/5)` should equal `0`. Let's see if it is: `16/5-16/5` does in fact equal `0`, which means that we were right!

Nice Job!