Answer:
7x
Step-by-step explanation:
Assuming your expression is :

Then we simplify as follows
since 
since 
since 
The base of the triangle could be 4, a side length could be 2. The other side might have the same side length as the first one, so 2 is a possible side length
2
At the end where it says 17-6+7 you were supposed to add them then subtract it (PEMDAS). So it would be 17-13=4.
Answer:
An expression
Step-by-step explanation:
Here is what I think it is. 7 is not an example of an expression because an expression is an equation without an equal sign. I believe that an expression has more than 1 number in it, so 7 is not an expression.
Answer:

<h3>x≤4000 is the right answer.</h3>