Question

-10x-8y=-20
20x+16y=4

Answer 1

`\left \{ {-10x-8y=-20\ \ \ \atop {20x+16y=4}} \right. \\\\ \left \{ {{-20x-16y=-40} \atop {20x+16y=4}} \right. \\+-------\\\\0\\eq-36\\\\There\ are\ no\ solution.`

Answer 2

solving for y:

20x + 16y = 4 20(1/5 - 4/5y) + 16y = 4
- 16y -16y 4 - 16y +16y = 4
20x = 4- 16y (-16y + 16y cancel out)
20 4=4
x = 2/10- 4/5y infinite solution

10x - 8y = 20 10(2/1 +4/5y) - 8y =20
+8y +8y 20 + 8y - 8y = 20
10x = 20 + 8y (8y - 8y cancels out)
10 20 = 20
x = 2/1 + 4/5y infinite solution