A person can do a job in 6 days. Another can do the same job in 4 days. If they work together, how long do they need to finish the job?

2.4 days

Step-by-step explanation:

Time working together,t ,is

1/t = 1/a+ 1/b  where a and b is the times working alone

1/t = 1/4 + 1/6

Multiply each side by 12t to clear the fractions

12t( 1/t )= 12t(1/4 + 1/6)

12 = 3t+2t

12 = 5t

Divide by 5

12/5 = 5t/5

2 2/5 =t

2.4 days

r(0,90)(x,y) . t(-5,0)

last option

step-by-step explanation:

∆def to ∆d"e"f"

- rotate 90 counterclockwise degrees

- then translated 5 to the left (x --> x - 5)

answer is the last option