Question 64361
I need to graph the folliwing equations. Identify the vertex, intercepts and equation of the axis of symmetry. If a value is irrational , find a decimal approximation.
: 
y = x^2 - 5x + 4
:
Make a table of x = -2 to + 6 and find y, the graph should look like this:
{{{ graph( 300, 200, -4, 8, -8, 8, x^2 - 5x + 4) }}}
:
Find the x intercepts:
x^2 - 5x + 4 = 0
Factor:
(x-4)(x-1) = 0
x = +4
x = +1
:
Find the y intercept, this occurs when x = 0
y = 0^2 -5(0) + 4
y = 4 is the y intercept
:
Find the axis of symmetry: 
using the form ax^2 + bx + c; axis of sym formula is x = -b/(2a)
In our equation a = 1; b = -5
x = -(-5)/(2*1)
x = +5/2
x = +2.5 is the axis of symmetry
:
Find the vertex, substitute for x = 2.5 and solve for y
y = 2.5^2 - 5(2.5) + 4
y = 6.25 - 12.5 + 4
y = -2.25
Vertex occurs at: x = +2.5, y = -2.25
:
you can confirm all this on the graph