Which of the following represents the function g(x)=2x²-20x+42 in vertex form? Identify the vertex.
1. g(x)=2(x+5)²-8;(-5,-8)
2. g(x)=2(x-5)²-8;(5,-8)
3. g(x)=2(x-5)²-8; (-5,-8)
4. g(x)=-2(x+5)²-8;(-5,-8)