Question

What is the solution of the system of equations `2x+3y=7, x+y=3`?

Answer 1

`(x,y)=(2,1)`

Explanation:

Given
[1]`color(white)("XXX")2x+3y=7`
[2]`color(white)("XXX")x+y=3`

Subtracting `2xx`[2] from [1]
#color(white)("XXX"){:(,,2x,+3y,,=,7),(underline(-),underline("("),underline(2x),underline(+2y),underline(")"),underline(=),underline(6)),(,,,y,,=,1) :}#

Substituting `1` for `y` in [2] gives
`color(white)("XXX")x+1=3`

`color(white)("XXX")rarr x=2`