72 persons have enough food for 7 days . but after one day they decided to finish the food in 3 remaining days . For if they invited more persons how many persons did they invite?

We have been given that

72 persons has enough food for 7days.

After 1 day they decided to finish the food in remaining 3 days.

We need to find number of invitees to finish the food.

After one day there are 72 people and they have food for 6 days.

If people are changed n times, time will change to (1/n) of initial time.

\frac{1}{n}\times 6\ =\ 3n1×6 = 3

Therefore n = 2

Total number of people needed  = n × 72

Total number of people needed = 72×2

Total number of people needed  = 144

Hence the number of invitees = 144 - 72 =72

72 people are invited to finish the food in 3 days

the polynomial is a perfect square trinomial of the form a^2-2ab+b^2:

option a. true

step-by-step explanation:

9x^2-12x+4

comparing with the form a^2-2ab+b^2

1.) a^2=9x^2

solving for a: square root both sides of the equation:

sqrt(a^2)=sqrt(9x^2)

a=sqrt(9) sqrt(x^2)

a=3x

2.) b^2=4

solving for b: square root both sides of the equation:

sqrt(b^2)=sqrt(4)

b=2

to be a perfet square trinomial 2ab must be equal to 12x. let's check:

2ab = 2 (3x) (2)

2ab = 12x

correct

to complete this square you have to rotate about the origin 270 degrees clockwise.