Aconstant force a={2,8} moves an object along a straight line from the point (3,6) to the point (10,14). find the work done if the distance is measured in feet and the force is measured in pounds.

The work done is 78 ft-lbs.

Step-by-step explanation:

The work W done by a force F in moving along a vector D is

In our case the displacement vector is

So the work done is

We know that the unit of force is pounds and the distance is mesuared in feet, then the work done is 78 ft-lbs.

given that triangle abc is transformed two times to get triangle

a"b"c"

first abc is transformed in to a'b'c' as follows:

the coordinates of a are (1,-1) and transformed into a'(-1,1)

similarly b (4,-2) became b'(-4,2) and

c(7,-2) became c'(-7,2)

i.e. (x,y) becomes (-x,-y)

this is nothing but reflection about a point here origin.

thus first transformation is reflection on the origin.

next is exactly shifting 3 units down

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