For this case we must algebraically rewrite the given expression. So:
x: It is the variable that represents an unknown number
"double a number" is represented as: 
"6 less than double a number" is represented as: 
So, the final expression is: 
If we want to rewrite the expression in an equivalent way, we take common factor 2:

Asnwer:

Equivalent expression: 
X + 3x + 4x = 56
8x = 56
x = 7
The shortest piece is 7 inches
The middle piece is 7*3 = 21 inches.
The longest piece is 4*7 = 28 inches
Check
7 + 21 + 28 = 56 It does check and the lengths are correct.
Hey the answer is 2713 cm
Answer:
180-146=34 146+34=180
Step-by-step explanation:

Change the mixed fractions to improper fractions.
To do this, multiply the whole number part by the denominator. Add that to the numerator. Then write the result on top of the denominator.
You would now have:

Change the division sign to a multiplication sign by turning the second fraction upside down.
That is,

The answer is:

This can be simplified to: