Why is (a - b) ^ 2 = a ^ 2 - 2ab + b ^ 2 also an expansion of a perfect square ? doch algebraic eypression

Twenty-five percent of the customers entering a grocery store between 5 p.m. and 7 p.m. use an express checkout. consider five randomly selected customers, and let x denote the number among the five who use the express checkout.

The distance between two points is 6.5cm and scale of map is 1: 1000 what's the distance between the two points

Find the unit rate. enter your answer as a mixed number. a fertilizer covers 2/3 square foot in 1/2 hour.