public boolean sumOf1stAnd2ndEquals3rd(int[] nums)

Given an array, all of whose lengths are 3,
return true if the sum of the 1st 2 elements equals the value of the 3rd.

Create a variable called sum and assign it the sum of the first two elements.
Use an if statement to check whether the sum == the 3rd element.

public boolean sumOf1stAnd2ndEquals3rd(int[] nums) {
  boolean equals = false;
  int sum = nums[0] + nums[1];
  if (sum == nums[2]) {
    equals = true;
  }
  return equals;
}