Esias 38:5

5 Thus saith the Lord, the God of David thy father, I have heard thy prayer, and seen thy tears: behold, I add to thy time fifteen years.

Esias 38:5 In-Context

3 Remember, O Lord, how I have walked before thee in truth, with a true heart, and have done that which was pleasing in thy sight. And Ezekias wept bitterly.
4 And the word of the Lord came to Esaias, saying, Go, and say to Ezekias,
5 Thus saith the Lord, the God of David thy father, I have heard thy prayer, and seen thy tears: behold, I add to thy time fifteen years.
6 And I will deliver thee and this city out of the hand of the king of the Assyrians: and I will defend this city.
7 And this a sign to thee from the Lord, that God will do this thing;

The Brenton translation of the Septuagint is in the public domain.