It takes 3 hours to fill a swimming pool and only 30 minutes to empty. a. Express this comparison as a ratio.

b. How long would it take to fill the pool half way?

c. How long would it take to empty a half full pool?

Step-by-step explanation:

Together they can fill 1.5 pools in 60 minutes. To fill one pool they take 2/3 of that time. That is 40 minutes.

i think it's ф or x=6,-6

step-by-step explanation:

-x^2=-36

x^2=-36

ф

or

if you mean by : -(x^2)=-36

it'll be: x^2=36

x=6,x=-6

hope it'll ! have a good day!

you for asking!