What does it mean for a point to be a solution to a linear equation?

What is this equation in point-slope form?

What is the solution set of the quadratic inequality x^2-5< or equal to 0

Players on the school soccer team are selling candles to raise money for an upcoming trip. each player has 24 candles to sell. if a player sells 4 candles a profit of$30 is made. if he sells 12 candles a profit of $70 is made