Question

Which equation represents "the sum of eight times a number and seven is twice the number"?

8(7 + 2N)
8N = 7 + 2N
7N + 8 = 2N
8N + 7 = 2N

Answer 1

If a number is N, what is eight times the number?

Answer 2

im not completely sure

Answer 3

Ok.
A number is 5
What is eight times that number?

Answer 4

40

Answer 5

its d

Answer 6

Right.
How did you do that?
You used multiplication.
Since the number was 5, and we wanted 8 times the number, you did 8 * 5.
Then you actually multiplied the numbers together and got 40.
That was correct. You could do the multiplication because you knew what both numbers were.

Answer 7

i whant to be sure its D

Answer 8

In our case, we don't know what number N is.
We just know N represents a number.
Then 8 times the number is simply 8 times N, which is 8 * N, or even more simply,
8N

Answer 9

Ignore direct answers, and learn from an explanation.

Answer 10

times is multiplacation 8n
then sum is addition 8n+7
twice a number is 2n
so 8n+7=2n

Answer 11

OK so far?
The unknown number is N.
8 times the number is 8N.

Answer 12

ok i see

Answer 13

Then the next step is:
"the sum of eight times a number and seven"
"Sum" is an addition, so we have:
8N + 7

Answer 14

i have anouther i whant to see if i got correct ill post it

Answer 15

Finally, the problem tells us that all that is twice the number.
That means 8N + 7 = 2N

Answer 16

Sure.

Answer 17

thanks alot mathstudent and da best

Answer 18

You're welcome.