Question

What is the vertex of `y= 3x^2+8x-7`?

Answer 1

Vertex is at `(-1 1/3, -12 1/3)`

Explanation:

`y = 3x^2+8x-7` . Comparing with standard equation `y = ax^2+bx+c` we get here `a=3 , b=8 , c= -7`

x co-ordinate of vertex is `-b/(2a) or - 8/(2*3) = -4/3 = -1 1/3` .

Putting the value of `x= -4/3` we get y co-ordinate of vertex as

`y= 3* (-4/3)^2 +8*( -4/3) -7 = 16/3-32/3 -7=-16/3-7 =-37/3 = -12 1/3`

Vertex is at `(-1 1/3, -12 1/3)` [Ans]