Did I do this right?
SA= 2(3 ½ + 11 ½ ) + 2(11 ½ + 11 ¾ ) + 2(3 ½ + 11 ¾ )
SA = 2(30) + 2(46.5) + 2(30.5)
SA= 60 + 93 + 61
SA= 214

- anonymous

- Stacey Warren - Expert brainly.com

Hey! We 've verified this expert answer for you, click below to unlock the details :)

- katieb

I got my questions answered at brainly.com in under 10 minutes. Go to brainly.com now for free help!

- anonymous

It looks like you already multiplied everything by two in the second step and put it in parenthesis. So, the additional 2 outside would not be needed at this point.

- anonymous

SA = 2(15) + 2(23.25) + 2(15.25) should be what you have in step 2.

- anonymous

|dw:1440632662356:dw|

Looking for something else?

Not the answer you are looking for? Search for more explanations.

## More answers

- anonymous

Basically step 2 should be SA = 2(15) + 2(23.25) + 2(15.25).

- anonymous

oh ok

- anonymous

So all i have to do is do SA = 2(15) + 2(23.25) + 2(15.25) and get my answer?

- anonymous

It looked like you accidentally multiplied by 2 going to that step and didn't realize it. Otherwise it would be (30) + (46.5) + (30.5). But that would require two steps.

- anonymous

correct

- anonymous

ok let me see what i get

- anonymous

ok 107?

- anonymous

That is correct. Also there is another way you could have done it which would give the same answer. Since everything is multiplied by 2, you can separate it and add everything else together.

- anonymous

yea i think i would have liked it better that way

- anonymous

SA= 2(3 ½ + 11 ½ ) + 2(11 ½ + 11 ¾ ) + 2(3 ½ + 11 ¾ )
SA = 2(3 ½ + 11 ½ + 11 ½ + 11 ¾ + 3 ½ + 11 ¾ )
SA= 2(53 ½)
SA= 107

- anonymous

i have another question can you just explain it to me what it means?

- anonymous

4. What is the surface area of the box if it is scaled up by a factor of 10?
its with the same question i asked before

- anonymous

I dont know what it wants me to do

- anonymous

Scaling something by a factor essentially means multiplying everything in the equation by that factor.

- anonymous

Since your factor is 10, you would simply multiply the Surface Area you already have by that factor (10).

- anonymous

so 107/10?

- anonymous

107 * 10

- anonymous

Out of curiosity, what was the original question that brought you to your work that you originally asked about?

- anonymous

1,070 right?

- anonymous

1. List the dimensions of your box. Be sure to include the units (in, cm, ft., etc.).
2. Describe the shape of the cross section when the box is cut parallel to the base.
3. What is the surface area of the box?
4. What is the surface area of the box if it is scaled up by a factor of 10?
5. What is the volume of the box?
6. What is the volume of the box if it is scaled down by a factor of ½?

- anonymous

OK, we need to back up to your original question as you set up the formula wrong.

- anonymous

ok ok
#work lol

- anonymous

hehe, it happens. Did you have to pick an item to measure or was dimensions already give to you?

- anonymous

i had to pick it

- anonymous

i just chose a binder

- anonymous

The formula for SA is 2 ( lw + lh + hw) or 2(lw) + 2(lh) + 2(hw) where the letters besides each other mean to multiply, not add.

- anonymous

Sorry, I didn't think about your equation when you asked, was just making sure the math was correct.

- anonymous

So, you would be multiply fractions by using those measurements.

- anonymous

Would you like to try something different or keep with the binder?

- anonymous

um i already have the measurements so keep it lol

- anonymous

Ok, so now you would have
SA= 2(3 ½ * 11 ½ ) + 2(11 ½ * 11 ¾ ) + 2(3 ½ * 11 ¾ )

- anonymous

135.125?

- anonymous

SA= 2(3 ½ * 11 ½ ) + 2(11 ½ * 11 ¾ ) + 2(3 ½ * 11 ¾ )
SA= 2(40.25 ) + 2(135.125 ) + 2(41.125 )

- anonymous

sorry, this place is annoying with fractions. .125 would be 1/8

- anonymous

433!

- anonymous

correct

- anonymous

yes!!

- anonymous

Now, since we are dealing with multiplying in our original equation instead of adding it changes the factor question somewhat.

- anonymous

how would it be different?

- anonymous

It is like saying SA = 2(10l * 10w) + 2(10l * 10h) + 2(10w * 10h)

- anonymous

essentially you are multiplying all of your measurements by 10 and changing the equation to those new measurements.

- anonymous

Since what really changes is you add are now multiplying by 10 * 10. So instead of 10 you would multiply your final answer by 100 instead. This part is simply a shortcut and if you are required to show your work you may have to multiply each measurement by 10 and redo the work.

- anonymous

SA= 2(35 + 115 ) + 2(115 + 117.5 ) + 2(35 + 117.5 )

- anonymous

This would be your new formula if you multiplied each side by 10.

- anonymous

oops, i made a mistake on that last formula, ignore it.

- anonymous

SA= 2(35 * 115 ) + 2(115 * 117.5 ) + 2(35 * 117.5 )

- anonymous

i was confused too lol
ok

- anonymous

There, fixed. sorry, was trying to copy and paste to save time and messed up. Will be extra careful from now on.

- anonymous

i got a crazy number...

- anonymous

13512.5??

- anonymous

Should have got 43300

- anonymous

hmm let me check my work

- anonymous

ok yep now i got 43300

- anonymous

multiplied wrong

- anonymous

SA= 2(35 * 115 ) + 2(115 * 117.5 ) + 2(35 * 117.5 )
SA= 2(4025 ) + 2(13512.5 ) + 2(4112.5)
SA = 8050 + 27025 + 8225
SA = 43300

- anonymous

ok, awesome

- anonymous

The biggest thing in math is to learn your formulas. As long as you start with the right formula, chances are you will do really well.

- anonymous

There are so many though.

- anonymous

I memorize most of them but i have trouble with long ones

- anonymous

Usually math teachers will give you a sheet with the formulas when you take tests so it is generally ok to use one when doing homework.

- anonymous

true lol

- anonymous

Don't worry, I think we all have that problem. Trying to remember all of the formulas can be tough. It doesn't hurt to try and set up your work from memory but before you actually start doing it, go back and make sure you had the formula right.

- anonymous

The volume of a rectangular prism is V=bh right?
i think im wrongl ol

- anonymous

Also, I find it helpful to right down the formula before starting the work.

- anonymous

Volume is in three dimensions so you would have a third measurement there. V = lhw

- anonymous

oh ok so it would be....
V= 11 3/4 x 11 1/2 x 3 1/2

- anonymous

right

- anonymous

ok so the answer to that is....

- anonymous

(doing the work lol)

- anonymous

LOL, see why i asked if you wanted to measure something else. :) Ask your teacher if it is okay to round up for future reference that way you aren't haven't to spend so much time on one problem.

- anonymous

472.938??

- anonymous

i will thx lol :)

- anonymous

Yes, basically.

- anonymous

Ok, what do you think it means to scale the box down by 1/2?

- anonymous

Subtract by 1/2 i guess?

- anonymous

Not quite. like I said before, a factor is a number you multiply by. So, you would multiply each of your sides by 1/2. Or, in other words, half of your original measurements.

- anonymous

OHhhhhhhh!

- anonymous

so half of 3.5, half of 11.5, and half of 11.75

- anonymous

ok that would beeee....

- anonymous

Hope you are ok with me doing decimals, should have asked I know your original measurements are in fractions. That doesn't confuse you, does it?

- anonymous

Not really i mean its the same thing

- anonymous

That is great that you can see that they are the same right away. That means you are doing really good in math :)

- anonymous

I guess lol im a 7th grader but i have 9th grade class. Algebra Honors

- anonymous

That doesnt mean i dont need help though lol.
1.75
5.75
5.875?

- anonymous

Correct, so do your Volume calculations with those new numbers and you will be good to go. And, you are right. We all need help sometimes.

- anonymous

ok ok the volume will be...

- anonymous

Eh idk about this answer V= 59.1171875

- anonymous

That is very close to exact. If I was you, I would just round that to 59. Also, you could probably round the last answer to 473.

- anonymous

Ok that would make more sense than to put the whole thing

- anonymous

Thank you so much for your time

- anonymous

Np, glad I could help.

- anonymous

I honestly do really appreciate it! :)

Looking for something else?

Not the answer you are looking for? Search for more explanations.