Let "a number" be represented with the variable x.
Solve the expression by breaking it apart:
"...the sum of four and a number": (x + 4)
"twice of...": 2(
"Twice of the sum of four and a number": 2(x + 4)
2(x + 4) is your answer.
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Step-by-step explanation:
Well in general, we can represent subtraction as: 
"z" represents the difference, and it really just represents x with y taken away. So if we were to "give back" this y value, we should get "x".
This means that: 
So one way to check, is adding the value that's being subtracted (y value) and the difference (z value), this should get you the value that is being subtracted from (x value). If you don't get the original value that's being subtracted from (x-value) then you know the answer you got is wrong.
Answer: 6x+18
Step-by-step explanation: Because of the Distributive property, you would multiply the 6 by the’x’ and 3, as they are in the parenthesis.
Answer:
3s + 3t
Step-by-step explanation:
To simplify this expression, all you need to do is distribute the 3, which means you basically multiply whatever is in the parentheses by 3:
(s + t) * 3 =
3s + 3t
And that is the simplified form for this expression.
Hope this helps :)