The difference in ' x ' (left or right) between D and F is 5 units.
The difference in ' y ' (up or down) between D and F is 2 units.
The straight-line distance between them is
√ (5² + 2²)
= √ (25 + 4)
= √ (29)
= 5.3851.....
or 5.4 (rounded to the nearest tenth)
