Lesson 22

Match the equation to the graph. Be prepared to explain your reasoning.

1. $y = x^2+x$
2. $y = \text{-}x^2 - 3x$
3. $y = (x-1)(x+5)$
4. $y = x^2 + 5x +1$

   A

   

   

   B

   

   

   C

   

   

   D

   

   

1. Graph the function $y = x^2 -10x + 16$.
2. Find the coordinates for the
   1. $x$-intercepts
   2. $y$-intercept
   3. vertex
3. Draw a dashed line along the line of symmetry for the graph.
4. What do you notice about the line of symmetry as it relates to the:
   1. vertex
   2. $x$-intercepts
5. Use the line of symmetry and the $y$-intercept to find another point on the parabola.

1. Write a function that is represented by a graph with $x$-intercepts at $(\text-3,0)$ and $(1,0)$.
   1. Without graphing the function, find the $y$-intercept. Explain or show your reasoning.

   2. Without using graphing technology, use the three points you know to sketch the graph of this function.

      

      

   3. What is the $x$-coordinate of the vertex? Explain your reasoning.
   4. Using the $x$-coordinate you found for the vertex, find the coordinate pair for the vertex.

2. 

   

   1. What do you know about the coordinates of the $y$-intercept?
   2. What do you know about the coordinates of the vertex?