Question

Solve graphically:$x+y=3;2x+5y=12$

Answer 1

$2x+5y=12$, we have $x+y=3$

when $y=0\Rightarrow x=3$, when $x=0\Rightarrow y=3$

$x03$

$y30$

$2x+5y=12\Rightarrow y=\frac{12-2x}{5}$

$x1-4$

$y24$

$\therefore$ The lines intersect at a point $p(1,2)$ Hence $x=1,y=2$