What should be done to solve the following equation?

d - 8 = 9

subtract 8 from both sides of the equation.
add 8 to both sides of the equation.
add 9 to both sides of the equation.
subtract 9 from both sides of the equation.

Which system of linear inequalities is represented by the graph?

This is so hard and it’s for a test

Suppose that one doll house uses the 1 inch scale, meaning that 1 inch on the doll house corresponds to 1/2 foot for life-sized objects. if the doll house is 108 inches wide, what is the width of the full-sized house that it's modeled after? in inches and feet.