Plz tell me the answer quick

What is the value of  y  in the solution to the system of equations? x  +  y  =  12x  –  3y  =  –30a. –8b. –3c. 3d. 8

Simplify 4 square root of 2 end root plus 7 square root of 2 end root minus 3 square root of 2 . (1 point) 2 square root of 8 8 square root of 2 8 square root of 6 6 square root of 8

The rumpart family is building a new room onto their house. the width of the new room will be 16 feet. the length of the room will be 4% greater than the width. write an expression to find the length of the new room. what will be the area of this new room?