Aclass of 19 pupils have five more girls than girls. let n =the number of boys

The areas of two similar triangles are 72dm2 and 50dm2. the sum of their perimeters is 226dm. what is the perimeter of each of these triangles?

Y+ 2/y is it a polynomial in one variable or not? and if so, why?

The width of a rectangle is half as long as the length. the rectangle has an area of 18 square feet. what are the length and width of the rectangle?