Answer: x=120; y=170.
Step-by-step explanation:
1) it is possible to make up the the system of two equations from these two given equations:
[tex]\left \{ {{5x+7y=1790} \atop {x+y=290}} \right.[/tex]
2) the solution of the system above:
[tex]\left \{ {{5x+7y=1790} \atop {5x+5y=1450}} \right. \ = > \ \left \{ {{2y=340} \atop {x+y=290}} \right. \ = > \ \left \{ {{y=170} \atop {x=290-y}} \right. \ = > \ \left \{ {{y=170} \atop {x=120}} \right.[/tex]
3) finally, (120;170).
