If 40% of a number is 56,what was the original number

[10 points, algebra 2-simplifying complex fractions]according to my answer key the restrictions are -1 and 4. but why not positive 1?

Vinay constructed this spinner based on the population of teachers at his school according to vinays model what is the probability that he will have a male history teacher two years in a row

What is the result of adding the system of equations? 2x+y=4 3x-y=6