Question

Find the number of the terms of the AP : 36,32,28.. which must be taken so that the sum is 180 . Explain the double answer.

Answer 1

Answer:

180=n/2(2a+(n-1)d

180=n/2(2(36)+(n-1)

180=n/2(72+(n-1)-4

180=n/2(72-4n+4)

180=n/2(-4n+76)

180×2=n(-4n+76)

360=-4n2+76n

4n2-76n+360=0

4(n2-19n+90)=0

n2-19n+90=0

n(n-9)-10(n-9)=0

n=9, n=10

mark me as a brainliest

Answer 2

steps are explained

here is your answer

I hope the answer is correct of your questions and answers