If the work required to stretch a spring 2 ft beyond its natural length is 12 ft-lb, how much work is needed to stretch it 9 in. beyond its natural length?

Work done = 1.69 lb-ft.

Step-by-step explanation:

Work required to stretch a spring 2 feet beyond its natural length W = 12 ft-lb

By Hook's law

12 =

12 = 2k

k = 6 lb per feet

Now we have to find the work done to stretch the spring 9 inch or feet beyond its natural length.

We again use the Hook's law.

lb-ft

Therefore, work done to stretch the spring 9 in. beyond the its natural length will be 1.69 lb-feet.

b

step-by-step explanation:

b) k’(6, 4); l’(3, 3)

step-by-step explanation:

a 270° clockwise rotation maps every point (x, y) to (y, -x). (it negates the x-coordinate and then switches it and the y-coordinate.)

this means the endpoints of the side congruent to kl, k' and l', would be mapped as:

k'(-4, 6)→(6, 4)

l'(-3, 3)→(3, 3)