If we assume that
- Brianna's house is at (1, 6)
- coordinates are (x, y) coordinates or equivalent
- "go right" means "go in the +x direction"
- "go down" means "go in the -y direction"
The difference in coordinates between Jordan's house and Brianna's house is
... (5,3) - (1, 6) = (5-1, 3-6) = (4, -3)
This means the x-value at Jordan's house is 4 more than at Brianna's house. One would have to go 4 blocks in the +x direction to cover that distance.
It also means the y-value at Jordan's house is 3 less than at Brianna's house. One would have to go 3 blocks in the -y direction to cover that distance.
To get from Brianna's to Jordan's, one path could be ...
... go right 4 blocks, go down 3 blocks.