4, has more whole number places than 40,000

What number should be added to both sides of the equation to complete this square? x^2-10x=7

How is working backward similar to solving an equation?

Let hh represent the number of hummingbirds and ss represent the number of sunbirds that must pollinate the colony so it can survive until next year. 6h+4s > 746h+4s> 74 this year, 88 hummingbirds pollinated the colony. what is the least number of sunbirds that must pollinate the colony to ensure that it will survive until next year?