1) in one minute for first wiil be 1/20
the other 1/30, it means that A paint in one minute 1/20 and B 1/30 then A+B in one minute 1/20 + 1/30 = 3+2/60 = 5 / 60, 5/60 = 1/12
if in one min they make 1/12 then in 12 min they paint all the wall
I'm pretty sure it's -4x.
Answer:

Step-by-step explanation:

Okay, so a kilometer=1000 meters, knowing that we can multiply 350*300 for the area, which would give us 105000 meters squared, then we divide 105000 by 1000, giving us 105 square kilometers.
Answer:
Part 4) 
Part 5) 
Part 6) 
Step-by-step explanation:
Part 4) Find ER
we know that
In the right triangle ERF
Applying the Pythagorean Theorem

substitute the given values

solve for ER


Part 5) Find DF
we know that
In the right triangle DRF
Applying the Pythagorean Theorem

substitute the given values


simplify

Part 6) Find DE
we know that
----> by segment addition postulate
we have

substitute
