Question

What is the vertex form of the equation?
y=x^2+4x-3
Can you explain how to do this?

Answer 1

To start off, let's factor out the two from 2x^2 + 4x.

y = 2*(x^2 + 2x) - 3

Answer 2

Now, we need to complete the square for what is in the parenthesis, so that we can get something off the form (x-h)^2.

y = 2*(x^2 + 2x + 1) - 3 BUT, we added a 1 in the parenthesis, which when multiplied by the two adds 2 to the right hand side, so we need to add 2 to the left hand side also, giving us:

Answer 3

y + 2 = 2*(x^2 + 2x + 1) - 3

y + 2 = 2*(x + 1)^2 - 3

y = 2*(x+1)^2 - 5

And there you go. :)

Answer 4

thank u