# [SOLVED] Expanding brackets and Simplyfying

• Feb 2nd 2009, 10:38 AM
Shandy
[SOLVED] Expanding brackets and Simplyfying
How can I simplyfy this:

4x(x+3)+4x2+x

and this:

c2 X 4cb

and this:

-9z(z3 - 4z+5)

Thank you!!!!!!!!!!!!
• Feb 2nd 2009, 10:45 AM
topher0805
Quote:

Originally Posted by Shandy
How can I simplyfy this:

4x(x+3)+4x2+x

and this:

c2 X 4cb

and this:

-9z(z3 - 4z+5)

Thank you!!!!!!!!!!!!

$
4x(x+3) + 4x^2 + x
$

Multiply:

$4x^2 + 12x + 4x^2 + x$

$
8x^2 + 13x$

Factor:

$x(8x+13)$

-----------------------------

c2 X 4cb <------ You need to clarify this.

-----------------------------

$-9z(z^3 - 4z+5)$

Multiply:

$-9z^4 + 36z^2 - 45z$

Factor:

$
-z(9z^3 - 36z + 45)$
• Feb 2nd 2009, 10:49 AM
masters
Quote:

Originally Posted by Shandy
How can I simplyfy this:

4x(x+3)+4x2+x

and this:

c2 X 4cb

and this:

-9z(z3 - 4z+5)

Thank you!!!!!!!!!!!!

Hi Shandy,

Distribute the 4x in the first one and then combine like terms.

$4x(x+3)+4x^2+x=4x^2+12x+4x^2+x=8x^2+13x$

In the second one,

$c^2 \cdot 4cb=4c^3b$

And the third one,

$-9z(z^3 - 4z+5)=-9z^4+36z^2-45z$

Remember the rule $a^m \cdot a^n=a^{m+n}$