[tex] \left \{ {{3f+4t=182} \ \ \ |(-1)\atop {7f+4t=382}} \right. \\\\\\ \underline{\left \{ {{-3f-4t=-182} \atop {7f+4t=382}} \right. } \\4f \ /=200 \ \ \ |:4 \\\\ \boxed{f=50 \ mingi \ fotbal} \\\\\\ 4t=182-3f \\\\ 4t=182-3*50 \\\\ 4t=182-150 \\\\ 4t=32 \ \ \ |:4 \\\\ \boxed{t=8 \ mingi \ tenis}[/tex]
3f+4t=182
7f+4t=382
4t=182-3f
4t=382-7f
De aici rezulta ca cele 2 ecuatii sunt egale.
182-3f=382-7f
382-182= 7f-3f
200=4f
f=200:4
f=50 mingi de fotbal
4t=182-3f
4t=182- 3 x 50
4t=182- 150
4t=32
t=32:4
t=8 mingi tenis
