SOLUTION: I am having trouble with these three problems. 1. Without graphing, find the vertex. f(x)= -(x + 3)^2 + 4 2. Without graphing, find the line of symmetry. f(x)=

Algebra.Com
Question 298717: I am having trouble with these three problems.
1. Without graphing, find the vertex.
f(x)= -(x + 3)^2 + 4

2. Without graphing, find the line of symmetry.
f(x)= 13/6(x-5)^2 + 5

3. Without graphing, find the minimum value.
f(x) = (x-1)^2 + 1

Answer by nerdybill(7384)   (Show Source): You can put this solution on YOUR website!

1. Without graphing, find the vertex.
f(x)= -(x + 3)^2 + 4
The "vertex form" of a quadratic/parabola is:

where
(h,k) is the vertex
.
So, starting with:
f(x)= -(x + 3)^2 + 4
we can rewrite to look like the "vertex form":
f(x)= -(x-(-3))^2 + 4
From inspection the
vertex is at (-3,4)
.
2. Without graphing, find the line of symmetry.
f(x)= 13/6(x-5)^2 + 5
Since the above is already in "vertex form" we immediately see that
vertex is at (-5, 5)
"line is symmetry" is then
x = -5
.
3. Without graphing, find the minimum value.
f(x) = (x-1)^2 + 1
Since the above is already in "vertex form" we immediately see that
vertex is at (-5, 5)
Since the coefficient associated withe the x^2 term is positive, we know it is a parabola that opens upwards. The vertex is then the minimum.
Therefore,
minimum value is k (of the (h,k) vertex)
Minimum is 5

RELATED QUESTIONS

1. Without graphing, find the vertex. f(x)=-(x+3)^2+4 (answered by richwmiller)
Without graphing, find the vertex. f(x) = 6(x - 4)2 -... (answered by Fombitz,nyc_function)
Without graphing, find the vertex. f(x)= 6(x-4)^2 - 9 I think it's... (answered by solver91311)
Without graphing, find the vertex. f(x) = (x + 3)2 + 3 Without graphing, find the... (answered by htmentor)
Without Graphing find the vertex please: f(x)=(x+2)^2-8... (answered by user_dude2008)
Without graphing find the vertex... (answered by Edwin McCravy)
I am having trouble with Graphing the quadratic function f(x)= x^2 + X - 12 (answered by josgarithmetic)
Without graphing, find the line of symmetry. f(x) = (x + 1)2 -... (answered by Fombitz)
Without graphing, find the vertex and the maximum and minimum value of f(x) f(x)=... (answered by KMST)