What's the algebraic expression for 'one half a number and 7'?

Question

Not positive on how to find an algebraic expression. Could you explain this problem and how you got the answer you did? :/ Help?

Answer 1

If that's the way it's worded, there could be more than one answer.

 

Since they're asking for one half a number, we can use a variable (let's say n) in place of where it says number.

 

So "one half a number" can be written as:

 

½ * n

 

"and 7" could be written as +7, since "and" means combining (addition) in this context.

 

Now the confusion rests in the order of operations. Is the wording saying one half of (n and 7) or (one half of n) and 7. If there are commas in the original wording it might help clarify.

 

The first interpretation would be written as:

½(n+7)

 

The second would be written as:

½n + 7

Answer 2

Kiley, algebra can be confusing. Remember when you first were learning math and you saw something like...

 

___ + 9 = 18

 

It would ask you to fill in the blank.

 

Now, we use a letter instead.

 

a + 9 = 18

 

What's the value of a?

 

So, if we say "a number" is x, then our expression is...

 

x/2 + 7

 

Later, they might say, "x is 8. Solve the xpression."

 

8/2 + 7 = 4 + 7 = 11

 

Make sense?