The store bought a pair of shoes fo $50, and sold it for $80. what percentage was the markup

Factorize: x^2+8x+10 i just solved it but i don't know if the process is correct

Solve the equation using the given values: x= -2.5; y= -7.51. 2xy + 2x²

For which of the following counts would a binomial probability model not be reasonable? a)the number of people in a classroom born in januaryb) the number of people in a classroom with red hair c) the number of people admitted to a hospital in a day with a particular disease d) the number of heart beats in a one-minute perio.