2. What it is used for… The Quadratic Formula is used to find an x- intercept if an equation won’t factor. Like this example. X^2 +3x-2 -2x^2 and 3x does no factor. Use the Quadratic Formulax= -b ± √b^2 – 4ac 2a
3. How to use it. An example of an equation is x^2+ 3x-2. To use the quadratic formula you have to figure out what the A, B, and C are. A is the coefficient in front of x^2. (1) B is the coefficient in front of x. (3) C is the lone number. (-2)
4. Substitution To use the quadratic formula you have to substitute the A,, B, and C in. Once you have done that you use the order of operations to solve what is inside. x^2 + 3x – 2 X= -3 ± √3^2 – 4(1)(-2)x=-3 ± √17 2(1) 2
5. To solve the rest of the equation When you simplify the equation as much as you can, then plug it into your calculator twice. Once doing addition and the next time doing subtraction. Make sure that you put a parenthesis around the radical. X= -3 + √17) x= -3 - √17) 2 2 Doing this will give you your 2 x- intercepts.
