If a= (7,9) and b= (3,12) what is the length of ab?

The length can be found using the Pythagorean Theorem...

c^2=a^2+b^2 and in this case:

d^2=(dx^2)+(dy^2)

d^2=(3-7)^2+(12-9)^2

d^2=-4^2+3^2

d^2=16+9

d^2=25

d=5 

So the length of AB=5 units.

It is true that organism need food. but cells do not need food. the energy required by the cell for various chemical activities is released by mitochondria in the form of atp (adenosine triphosphate). atp is know as energy currency of the cell.hope it