Functions Defined By Equations: solve f(x) = 0 for f(x) = x^  TOPIC_SOLVED

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Functions Defined By Equations: solve f(x) = 0 for f(x) = x^

Postby sk8rgirl130 on Fri May 01, 2009 6:43 pm

For each function, (a) find f(0), and (b) solve f(x) = 0
f(x) = x^2 - 13x + 40

:confused:

I completed (a) and got f(x) = 40.

I need help figuring out (b)
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Postby stapel_eliz on Fri May 01, 2009 7:01 pm

sk8rgirl130 wrote:For each function, (a) find f(0), and (b) solve f(x) = 0
f(x) = x^2 - 13x + 40

I need help figuring out (b)

Plug "0" in for "f(x)" to get:

. . . . .0 = x2 - 13x + 40

Then solve the quadratic equation by whatever method you prefer. You could solve by factoring, since x2 - 13x + 40 = (x - 5)(x - 8), or you could always use the Quadratic Formula. :wink:
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Re: Functions Defined By Equations: solve f(x) = 0 for f(x) = x^

Postby sk8rgirl130 on Mon May 04, 2009 4:45 pm

thanks soooo much. i cant believe i couldnt remember to do that. i guess it was just a hard day. thanks sooo much. i appreciate it. :D
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