# Algebra Review

• Aug 28th 2008, 06:10 PM
Casas4
Algebra Review
I cant make this problem work for whatever the reason is.
(2z)^(1/2)-(z+7)^(1/2)=1
For whatever reason i want to square all of it but then one i solve it down i get -6 and i know thats not right.
thanks to anyone
AC
• Aug 28th 2008, 06:18 PM
JOhkonut
Quote:

Originally Posted by Casas4
I cant make this problem work for whatever the reason is.
(2z)^(1/2)-(z+7)^(1/2)=1
For whatever reason i want to square all of it but then one i solve it down i get -6 and i know thats not right.
thanks to anyone
AC

Get one term on the other side...
$\displaystyle \sqrt{2z}=1+\sqrt{z+7}$
Then square. See if you can take it from there.
• Aug 28th 2008, 06:36 PM
Weezy
graphing problem
what is wrong with the graph to this equation?

+- the square root of 1-x^2
• Aug 28th 2008, 08:05 PM
Casas4
what do i do from here
Ok so when i square root both sides do i square root (1+(z+7)^1/2 or just (z+7)^1/2
When i tried doing it (1 +((z+7)^1/2))^2 i still couldnt get it to work.
Sorry for whatever reason i cant make this problem work.
• Aug 28th 2008, 08:54 PM
JOhkonut
Quote:

Originally Posted by Casas4
Ok so when i square root both sides do i square root (1+(z+7)^1/2 or just (z+7)^1/2
When i tried doing it (1 +((z+7)^1/2))^2 i still couldnt get it to work.
Sorry for whatever reason i cant make this problem work.

You're never going to square root anything in this problem. You're squaring both sides. For (1 +((z+7)^1/2))^2,
which is the same thing as $\displaystyle (1+\sqrt {z+7})^2$, you have to use FOIL by splitting the square into 2 binomials. $\displaystyle (1+\sqrt {z+7})(1+\sqrt {z+7})$ FOIL is the order of what terms to multiply when multiplying 2 binomials.

First - Multiply the first terms ($\displaystyle 1$ and $\displaystyle 1$)
Outer - Multiply the outer terms ($\displaystyle 1$ and $\displaystyle \sqrt {z+7}$)
Inner - Multiply the inner terms ($\displaystyle \sqrt {z+7}$ and $\displaystyle 1$)
Last - Multiply the last terms ($\displaystyle \sqrt {z+7}$ and $\displaystyle \sqrt {z+7}$)
• Aug 28th 2008, 10:07 PM
mr fantastic
Quote:

Originally Posted by Weezy
what is wrong with the graph to this equation?

+- the square root of 1-x^2

Do not post new questions in existing threads. Start a new thread.
Do not ask for help in Live Chat. Live Chat (as it clearly states) is for small talk. (Against my better judgement I have edited an answer into your chat).
Your question here makes no sense - it requires more information.