+59 How would I convert this equation to standard form? y = -2 (x - 6)^2 + 8
+118678
$$\\y = -2 (x - 6)^2 + 8\\
y=-2(x^2-12x+36)+8\\
y=-2x^2+24x-72+8\\
y=-2x^2+24x-64\\$$
+118678 Hi shadew,
Sorry I took so long to get back to you I have been busy today.
I am very glad that you asked - I like to get feed back :)
This is the long way I could have done $$(x-6)^2$$
$$\\(x-6)^2\\
=(x-6)(x-6)\\
=x(x-6)\;\;-6(x+6)\\
=x^2-6x\;\;-6x-36\\
=x^2-12x+36$$
Now $$(x-6)^2$$ is a perfect square. There is a short cut method.
$$\\(a\pm b)^2=a^2\;\pm\;(2*a*b)\;+\;b^2\\
so\\
(x-6)^2=x^2\;-\;(2*x*6)\;+\;6^2=x^2-12x+36$$
I sometimes use this method when I want to square numbers in my head
eg
$$\\23^2\\
=(20+3)^2\\
=20^2+(2*20*3)+3^2\\
=400+120+9\\
=529$$
