Can u Math Geniuses out there help me?????

Question

hi peoplez! i dont get how to do these problems can u like explain it to me step by step??i would appreciate it!!=)
3/4n+16=2-1/8n
1.03x-4=-2.15x+8.72

they are two different problems..

thanx guys i really appreciate it!
xoxoxo

so the second one is 4?ok i get it thanks so much for all of you guys help!!

Answer 1

Here is the BEST explanation:

Question 1:
3/4n + 16 = 2 - 1/8n

Add 1/8n to both sides:
3/4n + 1/8n + 16 = 2

Now subtract 16 from both sides:
3/4n + 1/8n = 2 - 16

Combine like terms:
3/4n + 1/8n = 6/8n + 1/8n = 7/8n
2 - 16 = -14

Now you have:
7/8n = -14

Multiply both sides by *8/7* (the reciprocal of 7/8) to make n = 1:
7/8n * (8/7) = -14 * (8/7)

Simplify:
n = -14 * 8/7 = -2 * 8 = -16
n = -16

(Note: the -14 in the numerator cancels the 7 in the denominator, making it a negative 2).

**Always** check your answer:
[(3/4 * -16) +16] = 2 - [1/8 * (-16)]
[(-12) + 16] = 2 - (- 2)
-12 + 16 = 2 + 2
4 = 4 <== checks!
------------------------------

Question 2:
1.03x - 4 = -2.15x + 8.72

Convert the entire equation to whole numbers.
(Multiply each term by 100):
103x - 400 = -215x + 872

Now, add 400 to each side:
103x = -215x + 872 + 400
103x = -215x + 1272

Next, add 215x to both sides:
103x + 215x = 1272
318x = 1272

Divide both sides by 318, so "x" equals 1:
x = 1272 / 318
x = 4

**Always** check your answer.
Plug the result into the original equation:
[1.03 * (4)] - 4 = -2.15 * (4) + 8.72

Simplify:
4.12 - 4 = -8.6 + 8.72
0.12 = -0.12 <== Checks!

xoxoxox to you too!
Good luck in your class.

Answer 2

You need to get all the n's or x's on the same side.
So:
3/4n + 16 = 2 - 1/8n
Add 1/8 n to both sides:
3/4n + 16 + 1/8 n = 2 - 1/8n + 1/8n
7/8n + 16 = 2
Subtract 16 from both sides:
7/8n + 16 - 16 = 2 - 16
7/8n = -14
Multiply both sides by 8
7/8 n * 8 = -14 * 8
7n = -112
Divide by sides by 7
7n / 7 = -112 / 7
n = -16
And then you can check:
3/4n + 16 = 2 - 1/8n
3/4 * -16 + 16 = 2 - 1/8 * -16
-12 + 16 = 2 + 2
4 = 4

Hope that helps...

Answer 3

I tried to scan the explanation I did on paper onto the computer and send it to you, but I couldn't. So I'll just explain to this way.

A. 3/4n+16=2 - 1/8n
1. Add 1/8n to both sides of the equation. (-1/8n and 3/4n). You add because it 1/8n is negative and to cancel a negative, you add its positive counterpart. Your new equation will read: 7/8n+16=2.

2. From there, you subtract 16 from itself and 2. (You don't subtract 2 because it is by itself on the other side of the equation.) Your new equation will read: 7/8n= -14.

3. All that's left to do is find n. You can find n by dividing -14 by 7/8.
4. n= -16. (To verify the answer, plug in -16 for n in the original problem: 3/4(-16)+16=2-1/8(-16). The new equation will read: -12+16=2- (-2) or 4=4.

Try the second one on your on and post an answer for me. I'll work on the second one and we'll just compare answers. If it turns out that you still need help, I'll walk you through the second one as well.

I hope my explanation for the first one is clear enough.

Answer 4

well girl, here goes...
for the first problem
3/4n+16=2- 1/8n

Now what you do is bring all the terms which have a constant to one side... in this case the terms with n in it

So, 3/4n + 1/8n = 2 -16 (Signs are changedwhen going from left to right and also when going from right to left)

so the equation becomes
7/8n = -14(After taking LCM which is nearly impossible to explain here)
then
7 = -14*8n
then n=7/-14*8
so,n=-1/16

for second equation
1.03x-4=2.15x+8.72
Bring all the terms with x on one sode

1.03x-2.15x=8.72+4
-1.12x=12.72
x=12.72/-1.12
x=11.35 (approx)

I hope you will understand the above steps on your own as its basic algebra but if you dont give that jackass teacher of yours a slap and tell him to teach it again. Bye

Answer 5

If you're having trouble with fractions and decimals, you can multiply them out as a first step to make the problem easier.

In your first problem, the common denominator is 8, so multiply EVERY TERM by 8. I'm emphasizing every term because some people only multiply the fractions. That will give you
6n + 128 = 16 - n
Since you have variables on both sides, move one of them. I would add n to both sides. That gives you
7n + 128 = 16
Now subtract 128 from both sides.
7n = -112
Divide by 7
n = - 16
The new equation should be easier to work with.
In the second one, all of your decimals are hundredths place. So multiply EVERY TERM by 100 and the decimals won't be there.
103x - 400 = -215x + 872
I'm sure you can go from there.

Answer 6

okay the first thing you want to do is get the variable all to one side,

3/4n +16 = 2-1/8n find the common denominator of the two fractions.
6/8n + 1/8n + 16 = 2 +1/8n -1/8n
7/8n + 16 = 2
7/8n = -14
O bother I think I mucked it up somewhere in there. sorry you've probably already got your answer by now anyway.

Answer 7

Right, looking at the first question first and all that:-

3/4n + 16 = 2 - 1/8n (you need to try and eliminate the fractions, make life so much easier)

so look to see what you can multiply both fractions by to remove them. I would suggest multiplying everything by 8.

This gives you -> 6n + 128 = 16 - 1n

You then need to move the n terms to one side and the numbers to the other to help solve the equation and ultimately find n.

So by moving the 1n term to the left. (-1n moved across the equals sign becomes +1n, so you can add it to the other 6n, to give you 7n)

This give you -> 7n + 128 = 16

No move the 128 across to the right. (+128 moved across the equals sign becomes -128, so you can add it to th 16, to give you -112)

This gives you -> 7n = -112

Therefore you can divide all terms by 7 to give you an answer of n=?

This gives you -> n = 16.

Now a similar approach can be used for the second question.

1.03x - 4 = -2.15x + 8.72

no need to eliminate the fractions this time though. Move the x terms to the left to start with. (-2.15x moved across the equals sign gives you +2.15x, which can then be added to the 1.03x term to give 3.18x)

This gives you -> 3.18x - 4 = 8.72

now moving the -4 term across to the right. (-4 moved across the equals sign gives you +4, which then added to 8.72 = 12.72)

This now gives you 3.18x = 12.72

Therefore if you divide 12.72 by 3.18, this will give you a value of x = 4.

Hope this answers your questions and explains how I arrived at the answers.

Answer 8

3/4n +16 = 2 - 1/8n

3/4n + 1/8n = 2-16

6+1 /8n = -14

7 = -14 * 8n

n= - 7/ 14* 8

n= -1/ 16

Answer 9

find a common denominator
6/8n + 16 = 2 - 1/8n
add 1/8n to both sides
7/8n + 16 = 2
subtract 16 from both sides
7/8n = -14
multiply by 8
7n = -112
divide by 7
n = -16

1.03x - 4 = -2.15x + 8.72
add 2.15x to both sides
3.18x - 4 = 8.72
add 4 to both sides
3.18x = 12.72
divide by 3.18
x = 4

sorry about my last answer...i misread -2.15x to be 2.15x (missed the negative)

Answer 10

3/4n+16=2-1/8n
First, you want to get N by itself, so subtract 16 from both sides.
Now you have 3/4n=-14-1/8n
add 1/8n to both sides to get N by itself
3/4n + 1/8n = -14
since the denominators are different, make 3/4 into 6/8 so you can add them easily. (3/4 and 6/8 are the same)
now you have
6/8n + 1/8n = -14
7/8n = -14
then multiply by 8 to get N by itself
7n = -112
divide by 7
n=-16

1.03x-4=-2.15x+8.72
First, add 2.15x to both sides to get x by itself
3.18x-4=8.72
now add 4 to each sides to get X by itself
3.18x=12.72
now divide by 3.18 to get x by itself
x=4