1. 9.3 Solving Quadratic Equations
Solve quadratic equations by graphing and using square roots.
9.3 Solving Quadratic Equations

2. Quadratic Equations Written in the form 𝑎 𝑥 2 +𝑏𝑥+𝑐=0
This form is called standard form of a quadratic equation.
Several methods for solving.
There can be 2, 1, or no solutions to a quadratic equation.
The solutions are called roots of the equation or zeros of the function

3. Graphing
In order to solve 𝑎 𝑥 2 +𝑏𝑥+𝑐=0, graph the function 𝑦=𝑎 𝑥 2 +𝑏𝑥+𝑐
Solutions are the x-intercepts

4. Practice Find the solutions by graphing: 𝑥 2 −1=0 𝑥 2 =0 𝑥 2 +1=0
Two solutions: 1, -1
𝑥 2 =0
One solution: 0
𝑥 2 +1=0
No solutions

5. Solving Using Square Roots
What are the solutions of 3 𝑥 2 −75=0?
Isolate 𝑥 2
𝑥 2 =25
Square root
𝑥 2 = 25
𝑥=±5

6. You Try!
𝑚 2 −36=0 ±6
3 𝑥 2 +15=0
No solutions
4 𝑑 2 +16=16

7. Assignment
Odds
P.564 #9-45