Answer:
The three consecutive integers are 19, 20, and 21. And 19 + 21 = 40.
Explanation:
Let the first integer be x.
The next consecutive integer would be x + 1 and the next x + 2.
The equation for the sum of the first and third integer equaling 40 can then be written as:
x + (x + 2) = 40
Solving gives:
2x + 2 = 40
2x + 2 - 2 = 40 - 2
2x = 38
x = 19