Question

Three times the difference of a number and eight is negative fifteen . Find the number?

Answer 1

3(n - 8) = -15
3n - 24 = -15
3n = -15 + 24
3n = 9
n = 9/3
n = 3 <==

Answer 2

Hey there!

"Three times..." means that you will multiply some part of your equation by 3. 

"...difference of a number and eight..." means that you will have (x – 8) in your equation. 

"...is negative 15" means that your equation will be set to equal 15. 

Altogether, your equation will be:

3(x – 8) = (–15)

All you need to do is solve for x. 

First, distribute the three to x and –8. 

3(x – 8) = (–15)

3x – 24 = (–15)

Now, add the 24 on the left side to both sides to cancel it out. 

(3x – 24) + 24 = (–15) + 24

3x = 9

Finally, divide both sides by 3 to cancel the three in 3x. 

(3x) ÷ 3 = (9) ÷ 3

x = 3

Your final answer will be 3. 

Hope this helped you out! :-)