Answer:
lol i failed miserably so hopefully this helps you not be like me
Step-by-step explanation:
The ratio of red sweets to yellow sweets is 12.
common difference d=3-1=2
first term a=1
an=a+(n-1)d
2n-1=1+(l-1)2
2n-1=1+2l-2
2n-1=2l-1
l=n
(i used l for number of terms)
number of terms=n
x = 11 or x = -1
(x-5)^2 = 36
(x-5) = 6 or (x-5)= -6
then x = 11 or x = -1