Question

How do solve the following linear system?: `x= y - 11 x, y = 4x + 4`?

Answer 1

`(x,y)=color(green)(""(1/2,6))`

Explanation:

Given
[1]`color(white)("XXX")x=y-11x`
[2]`color(white)("XXX")y=4x+4`

There are several ways to solve this, but it seems to be set up for substitution;
so, substituting, from [2], `4x+4` for `y` in [1]
[3]`color(white)("XXX")x=4x+4-11x`

[4]`color(white)("XXX")8x=4`

[5]`color(white)("XXX")x=1/2`

then, substituting, `1/2` for `x` in [2]
[6]`color(white)("XXX")y=4*(1/2)+4`

[7]`color(white)("XXX")y=6`

(or course, as always, you should plug these values back into both original equations to verify your results)