Answer:
60 minutes for the larger hose to fill the swimming pool by itself
Step-by-step explanation:
It is given that,
Working together, it takes two different sized hoses 20 minutes to fill a small swimming pool.
takes 30 minutes for the larger hose to fill the swimming pool by itself
Let x be the efficiency to fill the swimming pool by larger hose
and y be the efficiency to fill the swimming pool by larger hose
<u>To find LCM of 20 and 30</u>
LCM (20, 30) = 60
<u>To find the efficiency </u>
Let x be the efficiency to fill the swimming pool by larger hose
and y be the efficiency to fill the swimming pool by larger hose
x = 60/30 =2
x + y = 60 /20 = 3
Therefore efficiency of y = (x + y) - x =3 - 2 = 1
so, time taken to fill the swimming pool by small hose = 60/1 = 60 minutes
Answer:

Step-by-step explanation:
The given equation is

For this function to have an inverse, we must restrict the domain, say 
We interchange x and y to get,

We now make y the subject to get;


We divide through by 16 to get;

We now take the square root of both sides to get;


Since
, the inverse function is

Answer:
Step-by-step explanation:
Xét tam giác DAB có: P là trung điểm AD, M là trung điểm AB
=> MP là đường trung bình của tam giác DAB => MP//BD và MP=
BD (1)
Xét tam giác DBC có: N là trung điểm DC, Q là trung điểm BC
=> QN là đường trung bình của tam giác DBC => QN//BD và QN=
BD (2)
Từ (1) và (2) => vecto MP song song cùng chiều với vecto QN
và độ dài MP = độ dài QN =
BD
=> vecto MP = vecto QN
Tương tự xét các tam giác DAC và tam giác ABC => vecto MQ = vecto PN