Solving Quadratic Equations Using the Quadratic Formula (continued)
Let’s go through one more example using the Quadratic Formula.
Solve n2 + 2n + 93 = 0 using the Quadratic Formula.
a = 1, b = 2 and c = 93
Real World Application: Solving Polynomial Equations
John is standing at the top of a building 4 units high. He throws a ball off the roof and its path is defined by the function f(x) = -x2 + 4. How many units from the base of the building does the ball hit the ground?
In this example, the best way to solve is to set the function equal to 0. Why? Well, when the ball hits the ground, the y-value is 0!
-x2 + 4 = 0
-x2 = -4
x2 = 4
x = -2, 2 (Note: -2 is excluded, since we cannot have a negative distance)
Therefore, the ball lands 2 units from the base of the building.
Review Worksheet
Complete the review worksheet for this section before taking the quiz. Download the review worksheet, complete the questions, and then download the answer key to check your work. Make sure to ask your teacher any questions.