We have such system of eq [tex] \left \{ {{9x-2y=19} \atop {7x=21}} \right. [/tex] First lets solve second eq 7x=21 /:7 divide both sides by 7 x=3 Now we can substitute it to first equation 9x-2y=19 9*3-2y=19 27-2y=19 /-27 subtract 27 both sides -2y=-8 /:(-2) divide both sides by -2 y=4 - its the answer
