1. Graph y = x² + 6x - 16. Adjust the WINDOW to properly fit the graph.
a. Trace the graph and find the value of y when x = -7 from the graph.
b. What is the y-intercept of this graph? How is the answer compared to the constant of the equation?
c. Determine the x-intercepts. How are they compared to solving the equation by factoring?
d. Give the coordinates of where the minimum value of this graph occurs.
e. Solve x + 6x - 16 20.
f. Solver? + 6x - 16 <0.
2. Solve all real solutions x' + 3r - 7x = 15 to two decimal place by graphing y = x + 3x - 7x - 15 and
determine its zeros. Adjust WINDOW accordingly.
a. Why is find the zeros of y = x + 3x² - 7x - 15 the same as solving the equation x + 3x? - 7x = 15?
b. Solve the equation, x + 3x - 7x = 15, again by using the intersect function of the calculator.
Give the coordinates (to the two decimal place) where the minimum value of this graph occurs.
d. Solve x + 3x? - 7x - 15<0.
3. A number people were shipwrecked on an island. The population of the island slowly grew for 20 years until a
passing boat rescued the people. The population on the island can be modeled by the formula, P=200(1.1)',
where P is the number of years on the island and t is the years that they have been shipwrecked.
Why is 0 Sxs 20 an appropriate x range for your window?
b. What is an appropriate y range? How will ZOOMFit set a good #ange for you after you have put in the x
range (we used this on the last worksheet)?
How many people were originally shipwrecked? What time is this?
d. What is the population after 5 years? 18 years?
e. When is the population 300? When is it 1000?
