Question

What is the vertex form of `y= (5x - 1) (x+1)`?

Answer 1

The vertex form is `y=5(x+2/5)^2-9/5`

Explanation:

`y=(5x-1)(x+1) or y = 5x^2+4x-1` Now comparing withh the general form `y=ax^2+bx+c` we get `a=5; b=4 ; c= -1` The x cordinate of Vertex is `=-b/2*a or -4/10 =-2/5` To get y co-ordinate of veryex putting `x= -2/5` in the equation `y = 5*(-2/5)^2+4*(-2/5)-1 = 5*(4/25)-8/5-1= -9/5` So The vertex form is `y=5(x+2/5)^2-9/5`graph{5x^2+4x-1 [-10, 10, -5, 5]}[Answer]