9.2
Solving Quadratic Equations by Graphing
Solve the equation by graphing.
2
x - 2x = 8
Step 1: Move all terms to one side of the equal
sign so the equation is equal to zero.
Step 2: Write the related equation, y = x 2 - 2x - 8
Step 3: Graph the equation
Step 4: Look for the zeros (the x-intercepts)
The zeros are the solutions of the equation!
Graphing the Equation:
Axis of Symmetry:
Vertex:
y-intercept:
Another point:
**The zeros are the solutions to the equation,
so the solution(s) to the equation are:
Solve the equation by graphing:
x 2 + 36 = 12x
x 2 + 5x = -8