Question

y=3x^2+6x-10 find the value of x where y has the smallest value. What is the smallest value of y?

Answer 1

look for vertex

Answer 2

notice the parabola is opening up and so its smallest y value is the vertex. We now it opens up because the # in front of x^2 is positive

Answer 3

the x-value for the vertex is x=-b/2a where we have an equation of the form \[ax^2+bx+c=f(x) \]

Answer 4

identify b and a

Answer 5

but how do I get rid of the 3 to make x^2 by itself?

Answer 6

you don't need to do any separating. to find the vertex it is all plug and play.