Question

How do you solve the following system?: `2x +5y =-1 , -5x -3y = 2`

Answer 1

`x=-7/19" "` and `" "y = -1/19`

Explanation:

`2x+5y=-1 " " stackrel (xx 3) rarr " " 6x+15y=-3`

`-5x-3y=2 " " stackrel (xx 5) rarr " " -25x-15y = 10`
`color(white)(XXXXXXXXXXXXX)underline(color(white)(XXXXXXXXXX))`

`color(white)(XXXXXXXXXXXXXXX)-19x = 7`

`color(white)(XXXXXXXXXXXXXXXXXX)darr`

`color(white)(XXXXXXXXXXXXXXXX)x = -7/19`

Then from `2x+5y=-1` we find:

`y = 1/5(-1-2x)`

`color(white)(y) = 1/5(-1-2(color(blue)(-7/19)))`

`color(white)(y) = -1/19`