How do I find the roots and and coordinates of the vertex of the graph y = 2x^2 + 4x - 8 ?

y = 2x^2 + 4x - 8y = 2( x^2 + 2x - 4)Completing the square:y = 2( (x+1)^2 - 1 - 4 )y = 2(x+1)^2 -10the vertex of graph lies at the minimum value of y, and this occurs when x = -1:y = 2(-1+1)^2 -10y = -10therefore the vertex lies at coordinates (-1,-10).For the roots, let the equation equal 0:2(x+1)^2 -10 = 02(x+1)^2 = 10(x+1)^2 = 5(x+1) = ± sqrt(5)x = -1 ± sqrt(5)