What is the value of x that satisfies the following simultaneous equation:
x - y = - 2
5x + 8y = - 23
I have never been excellent at maths. So this might be the simplest simultaneous equation for you but for me I have no clue. I did do some prior research (again might sound like a dummy) and here's what I got on how to solve it:
5x + 8(x+-2) = -23
5x + 8x+-16 = -23
13 + -16 = - 23
13x + 16 = -23
5x = - 23
My working was from another site, I don't think I was on the right track so if it's wrong just ignore it :P
I updated the OP, my mistake I forgot to space it out. And yes it's two equations. I included the actual question if it helps. Thanks!
Another way to do this problem is to multiply the first equation by 8 to get 8x- 8y= -16. The reason for doing that is to get "-8y" which will cancel the "+8y" in the second. Adding the equation 8x- 8y= 16 to 5x+ 8y= -23 gives (8x+ 5x)+ (-8y+ 8y)= -16- 23 or 13x= -39. Now divide both sides by 13 to get x= -3.
Once you have x= -3, the equation x- y= -2 becomes -3- y= -2 or, adding 3 to both sides, -y= 1.