Add one to a number, then double the sum, and you get 56.

Question

how do i solve it and write it as a equation

(x+1)*2=56

1. divide both sides by 2
2. subtract 1 from both sides

you get x=27

For all of these questions just remember that when they say "a number" you should think of a variable like x or y. And when they say add you use a plus sign +, when they say difference use a - sign. When they say double its multiplication, etc.