Question 36349: Here I need to factor the quadratic expression completely, and find the roots of the expression.
135x^2 - 222x + 91 Answer by Earlsdon(6294) (Show Source):
You can put this solution on YOUR website! This is a hard one to factor but it can be done with a bit of trial & error:
The factors of 135 are:
1 X 135 = 135
3 X 45 = 135
5 X 27 = 135
9 X 15 = 135
The factors of 91 are:
1 X 91 = 91
7 X 13 = 91
You can try various combinations of these but the sum (or the difference) of the factors for the x-term must equal -222.
For example:
To find the roots, we must have an equation, so you can set the expression equal to zero. Factor. Apply the zero products principle. and/or
If then and
If then and
The factors are: (15x - 13) and (9x - 7)
The roots are: and
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