With Professor Owl Created by Robbie Smith
Quadratic Term: ax² Linear Term: bx Constant Term: c In order to have a solution, the line or parabola must touch the x-axis once or twice. If it doesn’t touch at all, there is no solution. You must also find the vertex and axis of symmetry
To find the points, you can make a table! XY Ex. x²+6x+14=y Then graph the results. This graph shows that there is no solution. Vertex: (-3,5) Axis or Sym: -3 Solution: None
Remember: Most equations can be factored, but not all equations can be factored. Here are some examples of factoring. Ex. (x+5)(3x-2)=0 X+5=0 3x-2= X=-53x=2 3 x=2 3 Unlike the last example which was already factored, you must factor this one. Ex. 16x² -9=0 (4x+3)(4x-3)=0 4x+3=0 4x-3= x=-3 4x= X=-3 x=3 4 4
More Examples Set the equation equal to zero Ex. x²+16=8x -8x -8x x²-8x+16=0 (x-4)(x-4)=0 x-4= x=4 Write in Proper Form Ex. 8x² -2=-2x +2x +2x 8x² -2=0 x²-16=0 (8x+4)(8x-4) 8 (x+4)(8x-4) x=-4 x=1 2 Ex. 3x²+6x=0 3x(x+2)=0 x= 0 x= -2
Examples of Perfect Squares x²+4x+4 (x+2)(x+2)=(x+2)² x²-8+16 (x-4)(x-4)=(x-4)² x²+14x+49 (x+7)(x+7)=(x+7)² To find the constant, do the following: Divide Linear by 2 Then square it. x²+4x+? 4/2=2 2²=4 x²+4x+4
Examples x²+4-10= x²+4x=10 4/2=2 2²=4 x²+4x+4=10+4 (x+2)²=14 √(x+2)²=√14 x+2=√14 x=-2+√14 x=-2-√14 3x²+6x-9= x²+2x-3=0 x²+2x+1=3+1 √(x+1)=√4 x+1=2 x+1=-2 x=1 x=-3
When you get an equation, it looks like this: ax²+bx+c When using the quadratic formula, use this formula: x=-b±√b²-4ac 2a Let’s see an example! The Discriminant: b²-4ac (Very Important) It tells you the numbers, root, and solutions. Sweet!
Discriminant: Negative-2 Imaginary Solutions Zero- 1 Real Solution Positive-perfect Square- 2 Reals Rational Positive-Non-perfect square- 2 Reals Irrational You must find the discriminant ! 3x²+6x-9=0 6²-4(3)(-9) = : Two Reals Rational x=-6±12 2(3) x= x= x=1x=-3