`y = -0.1x^2 + 3.2x - 3.5`
find the x-intercepts by factoring.
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Is this a trick question? I tried every factoring I could find of 3.5 and .1, but none of them would give me 3.2 when I FOILed to check my answer. I resorted to using the Quadratic Formula, and I found that the solutions are irrational numbers. If the solutions are irrational, then this problem cannot be solved by factoring.
I see. Can the x-intercepts be found any other way.
For any Quadratic, whether it is factorable or not, you can find the exact zeros by using the Quadratic Formula:
Where your `a` is your leading coefficient, or -0.1, your `b` is 3.2, and your `c` is -3.5. Just remember:
we can rwrite y so:
so `y=0 rArr` `x^2-32x+35=0`
are the solutions required: `x_1=30.86606875` `x_2=1.13393125`
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