B)
in a survey of people who like different languages in films, 50liked nepali, 40 liked english,
30 liked hindi, 24 liked nepali and english, 19 liked nepali and hindi, 13
liked hindi and english, 6 liked all three and 21 people were found not interested in
any language. find
(i)how many people did not like hindi films?
ii) how many people did not like both nepali and hindi films?

let's cover over the formula of the vertex:

y = a(x – h)^2 + k

in this formula, (h,k) are the vertex, always remember that the positive or negative value of the vertex is based on the sign it has.

for example, if the vertex is -3,-6 then both the x and y value would have the positive sign attached to it and if it were a positive x and y value, then a negative sign would be attached to it.

with that being said, for our problem the x value is a positive one so we are looking for a number with a negative sign next to it, in this case the first and second choice.

however, for the first answer choice it isn't quite part of the formula so we know that the answer choice correctly displays the x value.

to confirm, we can see if the -1 fits correctly with the second answer choice, and as mentioned above a negative number will have a positive sign attached to it. so, for our problem we can see that -1 has been changed to +1, so we can confirm that the second answer choice is correct.

hence, our final answer is y=(x - 1)^2 + 1

answer: 12   they all have at least 28 days

step-by-step explanation: haha