I need help please don’t scam or no brainlist

Two numbers have a sum of -19. one number is x. what expression represents the other number?

A50-foot ladder is leaning against a vertical wall. if the base of the ladder is 45 feet from the base of the wall, find the angle the bottling of the ladder makes with the ground.

At store a, erasers are sold individually. the cost y of x erasers is represented by the equation y=0.75x. the costs of erasers at store b are shown in the graph.