1 Derivan Oil Based Patina has now been discontinued and no longer in production. 2  Derivan CanvasJack, a unique artist quality range of stretched canvases and tensioning system. 3  Our Face & Body range has just being expanded with new Face Paint Markers and Wipes. Add even more fun to your face painting. 2  Derivan continues to expand its range of artists materials with the new, professional artist grade, Derivan Watercolours range. 3  Three new colours extends Derivan Block Ink range. 4  Just released, MM32 Light Modelling Paste a NEW modelling compound added to Matisse Mediums range.
You can think of the formula for finding the vertex of a quadratic function as being (x, y) = [(-b/2a), f(-b/2a)] . This just means that to get the y value, you have to find the x value based on the formula and then plug it back into the equation. Here's how you do it: 1  y = x 2 + 9x + 18.
From here, finding the vertex is very simple: take the value in the parentheses #(-2)#, and reverse the sign, so that now you have #2#. Congratulations, you just found your #x#-value of the coordinate pair. To find the #y#-value, just take the value of the constant, and don't change any signs; just leave it alone. Now you have all you need to create a coordinate pair. #(2, -3)# is the vertex, and lest's just confirm that by graphing the original equation. graph{y=x^2-4x+1}. And the vertex is #(2,-3)#!