Operators add and assignment

JavaScript
#1

Tell us what’s happening:
Hope all is well, I’m currently not understanding how to use operators. My attempts are below the modified line. Can someone please help me understand how to use operators when applying them, to a statement.

Your code so far


var a = 3;
var b = 17;
var c = 12;

// Only modify code below this line

a = a + 12;
b = 9 + b;
c = c + 7;


a += 3;
b += 17;
c += 12;

Your browser information:

User Agent is: Mozilla/5.0 (Windows NT 6.1; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/75.0.3770.100 Safari/537.36.

Link to the challenge:
https://learn.freecodecamp.org/javascript-algorithms-and-data-structures/basic-javascript/compound-assignment-with-augmented-addition/

#2

Why have you changed the numbers?

a = a + 12; // this add 12 to the variable a

a += 3; // this add 3 to the variable a
#3

What part don’t you understand?

#4