4 miles in 4 hrs.....4/4 =1...thats 1 mile per hr
for 2 hrs.....at 1 mile per hr = 2 miles <==
Aw you put the numbers in so a b c then you solve
For the transformation

the Jacobian is

with determinant

The vertices of the triangle in the
-plane are



Then the integral is

Translation in right or left causes the x coordinate to change while translation in up or down causes the y coordinate to change.
Moving left or down causes the coordinates to be going negative.
Moving right or up causes the coordinates to be positive.
Original point (10, 1).
Down 1 unit:
(10, 1 - 1) = (10, 0)
Left 7 units:
(10 - 7, 0) = (3, 0)
You end at (3, 0)