SOLUTION: Hello! Graph the following parabola. Calculate and identify vertex and intercepts in graph. Problem - y=x^2+4x+3 y= (x+1) (x+3) = Is this correct s

Algebra ->  Quadratic Equations and Parabolas -> SOLUTION: Hello! Graph the following parabola. Calculate and identify vertex and intercepts in graph. Problem - y=x^2+4x+3 y= (x+1) (x+3) = Is this correct s      Log On


   

Question 194613: Hello!
Graph the following parabola. Calculate and identify vertex and intercepts in graph. Problem - y=x^2+4x+3

y= (x+1) (x+3) = Is this correct so far? I'm not sure howto graph this parabola. Can you help me? Thank you!!!


Answer by Mathtut(3670) About Me  (Show Source):
You can put this solution on YOUR website!
first you have to rewrite this so that the variable y is positive and set this up to complete the square
:
y=-1%28x%5E2%2B4x%29-3%29
:
y=-1%28x%5E2%2B4x%2B4%29%2B4-3
:
y=-1%28x%2B2%29%5E2%2B1
:
vertex is at (-2,1)
:
intercepts are found by setting y to zero
:
we know it opens down because it is in the form y=x%5E2 and coefficient is a negative 1
:
0=x%5E2%2B4x%2B3--->%28x%2B1%29%28x%2B3%29=0 so x intercepts are -1,-3: (-1,0)(-3,0)
:
graph%28300%2C300%2C-10%2C10%2C-10%2C10%2C-x%5E2-4x-3%29