test.js

var numbers = [0,1,2,3,5,8,9,11];
var sum = 17;

function ifTwoNumbersEqualSum(arr, sum){
	
	var innerArr = [];
	
	for(var k = 0, len = numbers.length; k < len; k++){
		
		var difference = sum - numbers[k];
		
		if(numbers[k] <= sum && (difference + numbers[k] === sum) && numbers.indexOf(difference) > -1){
			
		   //console.log(numbers[k], difference);

           return true;
			
		}
				
	}
	
	return false;

}