The negative 2 tells us that the graph has a horizontal shift of 2 units to the right and the plus 5 tells us that the graph has a vertical shift up by 5 units.
A system of equations refers to a number of equations with an equal number of variables. We will only look at the case of two linear equations in two unknowns. The bracket on the left indicates that the two equations are intended to be solved simultaneously, but it is not always used.
