How do you graph and label the vertex and axis of symmetry of #y=(x+2)^2-3#?

1 Answer
Jan 4, 2018

Using the information given to you and a bit of expanding.

Explanation:

Lets start with the known information.

From this we can identify the the vertex of the graph which as we know would be

#(-2,-3)# The X value is negative as the bracket is equal to 0.

We can also work out the roots by solving for x with the given completed square. There set y = to 0 and solve,

#(x+2)^2-3 = 0#
#therefore (x+2)^2=3#
#therefore x+2= +-sqrt(3)#
#therefore x =-2+-sqrt(3)#

Now we have our roots of the graph.

Now finally its time for the y-intercept, this can easily be obtained by expanding out the given completed square.

#therefore (x+2)^2-3 = x^2+4x+4-3 = x^2+4x+1#

This #implies# that the y intercept #=(0,1)#
Now all we need to do is plot the key points and sketch the graph. graph{y=(x+2)^2-3 [-10, 10, -5, 5]}