# What is the vertex of #y=-2x^2 + 2x + 5 #?

##### 2 Answers

Aug 10, 2017

#### Explanation:

#"given the equation of a parabola in standard form"#

#"that is "y=ax^2+bx+c#

#"then "x_(color(red)"vertex")=-b/(2a)#

#y=-2x^2+2x+5" is in standard form"#

#"with "a=-2,b=+2,c=5#

#rArrx_(color(red)"vertex")=-2/(-4)=1/2#

#"substitute this value into the equation for the corresponding"#

#"y-coordinate"#

<

#rArrcolor(magenta)"vertex "=(1/2,11/2)#

Aug 10, 2017

Vertex is at

#### Explanation:

The axis of symmetry is also the x value of the vertex. So we can use the formula

Substitute

Therefore, the vertex is at