The lenth of the room is 3 times the width and the total area of the room is 12 square meters. what is the length of the living room

Name the most appropriate metric unit for each measurement

There are 15 plates and each plate is either 7 or 12 inches diameter. which systems of equations do you use to find the number of 7 inch plates, x and 12 inch plates, y

If f(x)=-x^2+6x-1 and g(x)=3x^2-4x-1,find(f+g)(x)