In a linear system that has a unique solution, why will the augmented matrix always have one more column than rows?

What is the missing constant term in the perfect square that starts with x^2 -20x

In triangle opq right angled at p op=7cm,oq-pq=1 determine the values of sinq and cosq

Do more republicans (group a) than democrats (group b) favor a bill to make it easier for someone to own a firearm? two hundred republicans and two hundred democrats were asked if they favored a bill that made it easier for someone to own a firearm. how would we write the alternative hypothesis?