square root
step-by-step explanation:
depends on how many days you are talking about
-12 > a
-11 > 1 + a
subtract 1 from each side
-11-1 > 1-1+a
option (b) is correct
to find the solution of this system, we need to convert it into reduced row-echelon form. we have,
after applying row operations r2 -> r2/2 and r3 -> r3/3, we get,