Question

The sum of 237 and six times the opposite of a number is 405. What is the number?
A)
-28
B)
-24
C)
30
D)
32

Answer 1

Let the unknown number be x.
Using x, how do you write the opposite of a number?

Answer 2

a negative number?

Answer 3

Yes, it's the negative of x, or simply
-x

Answer 4

6x

Answer 5

Now we have the opposite of a number is -x.
How do you write "six times the opposite of a number"?

Answer 6

Be careful. 6x is simply "six times a number."
We need 6 times the opposite of a number.

Answer 7

6x+n?

Answer 8

The opposite of a number is -x.
We need six times -x

Answer 9

We are not adding anything yet.

six times a number is 6x
the opposite of a number is -x
six times the opposite of a number is 6 * (-x)

ok so far?

Answer 10

yes

Answer 11

OK. Now we deal with 237.
The "sum" means an addition.
The sum of 237 and six times the opposite of a number is

237 + 6 * (-x)

Ok?

Answer 12

ok

Answer 13

Now we finally take care of the 405.

237 + 6 * (-x) = 405

Now we have an equation. We can solve the equation and find the number.

Answer 14

First, let's simplify 6 * (-x) into simply -6x

237 - 6x = 405

Now we subtract 237 from both sides.

Answer 15

237 - 6x = 405
-237 -237
----------------
-6x = 168

Answer 16

Now we divide both sides by -6

-6x/(-6) = 168/(-6)

x = -28

Answer 17

The number is -28.

Answer 18

yup that exactly what i got

Answer 19

Great.

Answer 20

thanks for the help really appreciated that