Answer:
So, the vertex form of your function is f(x)=2*(x+2)^2+7
The vertex is at (-2|7)
This is the graph of your function.
vertex point at (-2|7)
Explanation:
f(x)=2*x^2+8*x+15
f(x)=2*(x^2+4*x+15/2) ( Factor out )
f(x)=2*(x^2+4*x+(2)^2+-1*(2)^2+15/2) ( Complete the square )
f(x)=2*((x+2)^2+-1*(2)^2+15/2) ( Use the binomial formula )
f(x)=2*((x+2)^2+1*7/2) ( simplify )
f(x)=2*(x+2)^2+7 ( expand )