What do the significant figures in a measurement include

If f(x)=2x^6+x^2+2 then what is the remainder when f(x)is divided by x+2

Arectangular exercise mat has a perimeter of 36 feet the length of the mat is twich the width writeand solve an equation to determine the length in feet. of the mat then find the area in square feet of the mart

Asystem of equations has 1 solution.if 4x-y=5 is one of the equations , which could be the other equation ?