Find the vertex of the graph of the equation $y = -2x^2+8x-15$, I've tried this problem and I got (-2, -23) every time, I don't see where I'm going wrong, I need some help with this problem.

icecreamlover Jul 2, 2021

#2**+2 **

The x coordinate of this dome shaped parabola's vertex will be given by x = - b/2a where b = 8 and a = - 2

x = 2

use this value in the equation to calculate the y coordinate as - 7

ElectricPavlov Jul 2, 2021

#5**+4 **

Hey there, ICL!

So, sometimes when you can't solve an equation, you can plug it into a Desmos Graphing Calc and then you'll be able to see the vertex.

EP is right about this one, x=2 and y= -7; here's the link to the graph: https://www.desmos.com/calculator/9nnq18slcn.

Hope this helped! :)

( ﾟдﾟ)つ Bye

TaliaArticula Jul 2, 2021