Homework Help: math

Posted by miah on Tuesday, February 22, 2011 at 6:32pm.

When you subtract 2 from a number, double the difference, and then add 7, you get 57. What is the number?

math - Helper, Tuesday, February 22, 2011 at 6:42pm
n = the number
n - 2 = subtract 2 from the number
2(n - 2) = double the difference
2(n - 2) + 7 = then add 7

2(n - 2) + 7 = 57
2n - 4 + 7 = 57
2n + 3 = 57
2n = 54
n = 27

The number is 27

Related Questions

math - When you subtract 2 from a number double the difference and then add 7 ...
Math 213 Elementary Math - 20. Think of a number. Add 7. Double the result. ...
elementary - Think of a number. Add 7. Double the result. Subtract 8. Double the...
Its math, cmon answer!!! - This is my HW problem; I'm thinking of a number. ...
Math - Add one to a number, then double the sum, and you get 56. how do i solve...
arithmetic - How does this work “Think of a #. Add 7. Double the result. ...
math - Think of a number. Add 17. Double the result.Subtract 4. Double the ...
Algebra - How do I express this in algebraic form? And could you please explain ...
math - What are the divisibility short cuts that help you out? Odd numbers can ...
ALGEBRA - can you help me with this. d dont get it at all :( let n be the number...

For Further Reading

First Name:
School Subject:
Answer: