Arectangular field has an area 28800 sq. meter. its length is twice as long as its width. what is the length of its sides?

Let 
x> the length side of rectangle
y> the width side of rectangle

we know that
x=2y> equation 1
area=x*y> 28800=x*y> equation 2
substitute 1 in 2

28800=[2y]*y> 28800=2y²> y²=14400> y=120 m
x=2*y> x=2*120> x=240 m

the answer is
the length side of rectangle is 240 m
 the width side of rectangle is 120 m

Look, when you want to do something like put it like x^2. x2 could mean x² or x₂. so to clear confusion, know the notation. to find the product multiply the x's and you get -8x and the y's and you get 6y. since it's all being multiplied it is just -8x6y, or answer a. although the better answer is -48xy(combining -8 and 6) because you should multiply constants whenever you can.