Answer: a=-3, b=-2, c=-4
Explanation:
Multiplying the bottom equation by 4, we get -4a+16b+8c=-52. Adding this to the first equation gives us 21b+2c=-50.
Multiplying the bottom equation by 3, we get -3a+12b+6c=-39. Subtracting this from the second equation gives us -14b+c=24. Multiplying this by 2, we get -28b+2c=48.
Subtracting the equations -28b+2c=48 and 21b+2c=-50, we get -49b=98, meaning b=-2.
Substituting this into 21b+2c=-50, we get 21(-2)+2c=-50, and thus 2c=-8, and c=-4.
Substituting these values into the first equation, we get 4a+5(-2)-6(-4)=2, and thus 4a+14=2, meaning 4a=-12, and a=-3.