Answer:
Steps:
Factor - Apply AC Method
Look at the coefficients
A=1, B=18, C=77
Find factors of AC that equal 77
{1,7,11,77}
Find pairs of the above factors, which, when multiplied equal 77.
{1*77, 7*11}
Which pairs of these factors have a sum of 18?
Found:
7+11=18
Split the middle term to use above pair
n^2+(7n+11n)+77
Factor n out of the first pair
n(n +7)+(11 n+77)
Factor 11 out of the second pair
n(n+7) + 11(n+7)
n+7 is a common factor
Group common factor
(n+11)(n+7)
Set each factor equal to 0. Then solve for n.
n = -7, -11