How do you find the vertex and intercepts for x^2-4x+y+3=0?

1 Answer
Jun 8, 2018

See graph

Explanation:

x^2-4x+y+3=0

first put in standard form:

y=-x^2+4x-3

y-intercept, set x=0 and solve for y

y=0^2+4(0)-3

y=-3

x-intercept(s) if they exist, set y=0 and solve for x

0=-x^2+4x-3

factor:

0=-(x - 1)(x - 3)

x=1 and x=3

Axis of Symmetry (aos) in the form ax^2+bx+c

aos = (-b)/(2a)

y=-x^2+4x-3

aos = (-4)/(2(-1))

aos=2

Finally find the vertex it is a minimum if a>0 a maximum if a<0

vertex = (aos, f(aso))

vertex = (2, f(2))

vertex = (2, -2^2+4*2-3)

vertex = (2, 1) is a maximum.

graph{-x^2+4x-3 [-7.21, 12.79, -8.2, 1.8]}