Jesus told us that we could combine our faith with another's when
praying for God's supernatural intervention in our lives. The two
people must be aligned in belief, thought and in wanting the same
result from God for the prayer, of course.
This prayer Jesus says is for two people to agree on what they are asking for and to bring that request to God. It could be called a prayer of petition or a prayer of faith according to your thoughts or even a prayer of agreement.
The interesting thing to me is that Jesus did not say tell everyone you know or everyone in the church and ask them to pray for you. There could be good reasons for that. Maybe in some cases a majority would not be in agreement regarding your request. Maybe many would be more in agreement with the doctor's negative report than in your belief that God would heal you. Maybe many would be of the belief that God is kicking back and taking a rest and isn't healing in this age, since doctors are so good.
Whatever the mix of beliefs, when you throw a prayer request out to the 'world', you may get more people speaking of death than of life and the scriptures tell us that, "death and life are in the power of the tongue".
And, the disbelief of others can stop healing miracles being manifest.
Mar 6:4-6 And Jesus said to them: A prophet is not without honour, but in his own country, and in his own house, and among his own kindred. And he could not do any miracles there, only that he cured a few that were sick, laying his hands upon them. And he wondered because of their unbelief.....
So, it's very possible Jesus knew what he was talking about and you should select carefully the person/people who is/are of like mind and faith as yourself and ask them to agree with you for your healing or other request! When you do God says through Jesus....
Matt 18:19 If two of you shall agree on earth as touching any thing that they shall ask, it shall be done for them of my Father which is in heaven.
Best wishes for Grace and the Peace of Jesus.