Please help me with this question! I don't know what to do!
The diameter of circle center Z is 5in. What is its area in terms of pi?

Question

Please help me with this question! I don't know what to do!
The diameter of circle center Z is 5in. What is its area in terms of pi?

whpalmer4 · Answer

$$d = 2r$$$$r=\frac{d}2$$$$ A = \pi r^2 =\pi(\frac{d}2)^2 =\frac{\pi d^2}{4}$$
Plug in 5 inches for the value of $d$

anonymous · Answer

I got 25. Is that right?

whpalmer4 · Answer

How do you figure that?  Can you show me your work?

whpalmer4 · Answer

Don't bump the post, answer my question...

whpalmer4 · Answer

If you show me where you made a mistake, we can clear up the misunderstanding.  If you just get someone else to give you the answer, you'll have the answer, but no understanding.

whpalmer4 · Answer

For starters, if someone says "give me in terms of " your answer needs to have in it...

anonymous · Answer

Sorry. That was an accident. I'm trying to redo it because it make sense to me. This time I got 2.5^2

whpalmer4 · Answer

I still don't see $\pi$ in there anywhere...and the number isn't right either.  can you please show me your work, as I asked?

whpalmer4 · Answer

Sorry, the number will be right.  Need to clean my screen, it looked like 2.6^2!

anonymous · Answer

Okay. So I pIuggd in 5 into 'd' as you've asked. 
5=2r so then I did this:
r=5/2=2.5
Then I got lost at the last part.

whpalmer4 · Answer

Okay, I then gave you a formula that used d in place of r, didn't I?  You can plug 5 directly into that:

$$A = \frac{\pi d^2}{4} = \frac{\pi(5)^2}{4} =$$?

anonymous · Answer

So (5)/4 means 25/5 right? I just want to make sure I'm doing this right.

whpalmer4 · Answer

What is $(5)^2$?

whpalmer4 · Answer

25, right?  so $$\frac{(5)^2}{4} = \frac{25}{4}$$

whpalmer4 · Answer

So the answer is $$\frac{25\pi}{4}$$or if you want a decimal expression you could write $$6.25\pi$$but most people would prefer the fraction, I think.

whpalmer4 · Answer

Depends on what you're going to do with the result — if you are computing a number, then the decimal might be preferable.  If you're doing some more algebra, the fraction might be better so you could spot cancellation.

anonymous · Answer

Okay. I got it right then. Thanks so much and sorry for all the frustration.

whpalmer4 · Answer

You're welcome. Sorry for misreading your result!