Can someone me were doing cinvert customary units of weight

X+y=-4 x-y=2 use elimination with adding and subtraction

Which rule describes the composition of transformations that maps ajkl to aj"k"l"? ro. 900 o to, -2(x, y) to, -20 ro, 900(x, y) ro, 9000 t-2. o(x,y) t-2, 00 ro, 900(x, y)

Interpret the following expression (5y^2-7)^3/(2y)^2