For each rule below, make a table of $x$- and $y$-values and then graph the rule on graph paper. Label each graph with its equation.

3. Compare the graphs. What do you notice?

   Hint (c):

   What are the shapes of the graphs of part (a) and part (b)?

   Answer (c):

   The $y=x^2$ graph points upward and the $y=−x^2$ graph points downward.

4. For the graph of $y=x^2$, estimate the $x$-values corresponding to $y=5$.

   Hint (d):

   Estimate the $x$-value where the line $y=5$ intersects the parabola. (See graph for the line $y=5$)

5. For the graph of $y=−x^2$, estimate the $x$-values corresponding to $y=−10$.

   Hint (e):

   See the hint in part (d).