Question

How to solve 5x + 7y = 1790 and 1x + 1y = 290 algebraically

Answer 1

Answer: x=120; y=170.

Explanation:

1) it is possible to make up the the system of two equations from these two given equations:

`\left \{ {{5x+7y=1790} \atop {x+y=290}} \right.`

2) the solution of the system above:

`\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.`

3) finally, (120;170).

Answer 2

Explanation: