Question

Two window washers start at the heights shown. One is​ rising, the other is descending. How long does it take for the two window washers to reach the same​ height? Explain.

21 ft high

rising 8 in./s

50 ft high

descending 11 in./s

After t​ seconds, the height of the rising window washer is exactly

nothing ​feet, and the height of the descending window washer is exactly

nothing feet. Setting these expressions equal to each other and solving for t yields the exact value t

nothing. Rounding to one decimal​ place, the window washers reach the same height after about

nothing seconds.

​(Simplify your​ answers.)

Answer 1

Answer: 18.32secs

Explanation:

given data:

first washer

21 ft high

rising 8 in./s

second washer

50 ft high

descending 11 in./s

Solution:

initial height of first washer = 21 feet

1feet = 12inches

21 * 12 = 252inches

decending at a pace of 8inch/secs

= 252 + 8x

initial height of second washer

= 50 feet

= 50 * 12

= 600inches

descending at a pace of 11inch/secs

= 600 + 11x

At what time would they meet

252 + 8x = 600 + 11x

collect like terms

8x + 11x = 600 – 252

19x = 348

divide both sides by 19

19x/19 = 348/19

x = 18.32secs