If y directly proportional to x, and y =56 when x =6, what is the value of x when y =84?

This question awards 100 ! i really don’t want to fail i will also mark you !

The area of a rectangle is 54x^9y^8 square yards.if the length of the rectangle is 6x^3y^4 yards,which expression represents the width of the rectangle in yards

Which has the greater energy, light of wavelength 519 nm or light with a frequency of 5.42 x 10^8 sec^-1?