Factored Form Equations
For Quadratic Equations you can calculate the factored form. First I will list the terms for the parts
- Quadratic Term (ax²)
- Linear Term (bx)
- Constant Term(c)
Give the equation
y = x² - 3x -10
This can be written like this
y = (x -5)(x+2)
The way to approach it is to identify the factors (numbers) when multiplied together add up to the constant (-10) part of the equation and when added together equal the linear (-3x) part of the equation
A more complex quadratic could be
y = 3x² + 8x + 4
Here we have to multiply the Quadratic Terms number with the constant i.e. 3 x 4 = 12. Then repeat above to find factors which add up to the linear part of the equation but this time we write it linear part split.
y = 3x² + 6x + 2x + 4
Now we look for common factors
y = 3x(x + 2) + 2(x + 2)
Now we can use q to equal x + 2
y = 3xq + 2q
Which factoring out q this can be written as
y = q(3x + 2)
And we know q = x + 2 so we now have
y = (x + 2)(3x + 2)
And another example
y = 2x² - x - 15
y = 2x² - 6x + 5x - 15
y = 2x(x -3) + 5(x -3)
y = 2xq + 5q
y = q(2x + 5)
y = (x - 3)(2x + 5)