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jahaira1994
May 11, 2009, 06:03 PM
I need homework help
[F]lesson 9.6 worksheet

1. 2x^2-27x+13=
2. 2n^2+13n-7=
3. 5x^2+20t+11=
:confused:
:confused:
:rolleyes:
:confused::eek:

Perito
May 11, 2009, 08:04 PM
2x^2-27x+13=0

2n^2+13n-7=0

5x^2+20x+11=0

These are known as quadratic equations. One way to solve them is to factor them.

2x^2-27x+13=(x-13)(2x-1)=0

If the product of two numbers equals zero, then at least one of the numbers is zero. So,

x-13=0 or 2x-1=0

x=13 or x=-\frac 12

The other two problems are solved in the same way.

There is also a quadratic equation that will solve them directly.

For a general quadratic equation,

0 = ax^2 + bx + c

The roots of the equation are given by

X = \frac {-b \pm \sqrt{b^2-4ac}}{2a}

jahaira1994
May 13, 2009, 03:29 PM
Thanks for the help...