What is the vertex of # y= 2(x-5)^2-5x^2-x-1#?

1 Answer
Jan 20, 2016

The vertex is # (-7/2, 343/4)#

Explanation:

First expand the equation to get rid of the brackets and into standard form. The expression can then be rearranged into vertex to identify the vertex.

#y = 2(x^2 -10x +25) - 5x^2 - x -1#
#y= -3x^2 -21x +49#
#y = -3(x^2 +7x) +49#

#y = -3(x+7/2)^2 +147/4 + 49#
#y = -3(x+7/2)^2 +343/4#

The vertex is # (-7/2, 343/4)#