Question

Max or min value y=3x^2+6x-5

Answer 1

`y = 3x^2+6x-5`

For a parabola
`ax^2+bx+c` the vertex's x equals:


`(-b)/(a)`


`a = 3, b =6`


`x = (-6)/(2*3)`

refine:


`x = -1`

Plug in x = -1 to find the y value :


`y=3(-1)^2+6(-1)-5`

refine :


`y = -8`

Therefore the parabola vertex is :


`(-1,-8)`

if a < 0 , then the vertex is a maximum value

if a > 0, then then vertex is a minimum value

a=3

Therefore
`(-1,-8)` minimum

hope this helps!