What is 6900g converted to kg???

Sal is tiling his entryway. the floor plan is drawn on a unit grid. each unit length represents 1 foot. tile costs $1.35 per square foot. how much will sal pay to tile his entryway? round your answer to the nearest cent.

Akitchen floor is made up of tiles that are in the shape of the triangle shown there are 40 tiles on the kitchen floor what is the total area of the floor

Does anyone know how to solve and graph this: 4 + | a + 2 | < 7the only part i don't get is the "4 +"