Thursday

April 17, 2014

April 17, 2014

Posted by **Amie** on Tuesday, October 4, 2011 at 12:27am.

f(x) = −x2 + 10x

- Pre-Calculus -
**drwls**, Tuesday, October 4, 2011 at 6:43amAll you have done is define f(x).

There is no "solution"

If you had written

f(x) = (any constant),

there would be a solution.

- Pre-Calculus -
**Steve**, Tuesday, October 4, 2011 at 11:24amNow, if you want to solve f(x) = 0,

f(x) = -2x(x-5)

so, f=0 when either factor is zero. This is why we always set f(x) = 0 to solve for x, because the only time a product of numbers is zero is when one of them is zero. If we had -2x(x-5) = 12, well, that doesn't help us because there are lots of numbers that multiply to equal 12. But if the product is zero, then one of the factors must be zero.

so, x=0 or x=5 will make f(x) = 0

**Related Questions**

Pre-Calculus - How do I write the quadratic function f(x) = 1/2 (6x^2 - 24x + 22...

Pre-Calculus - Find a quadratic function f such that f(1)=3, f(2)=5/2, f(-1)=1 I...

Calculus - An important problem in mathematics is that of root finding: that is...

math - 1.How is the maximum or minimum point of the original quadratic function ...

pre-ap pre calculus - To solve an equation by finding x-intercepts, Cynthia ...

calculus - Quadratic function written in standard form where a, b, and c are ...

Pre-Calculus - Graphing Polynomials Decide whether each of the following is ...

Quadratic Functions - Please explain to me how to do the following problems, I ...

pre calc - Solve: (x+5/x)+(6/x-4)=(-7/x^2-4x) I multiplied the entire function ...

Pre Calc still confused - Solve: (x+5/x)+(6/x-4)=(-7/x^2-4x) I multiplied the ...