Alocal electronics store raised its prices on headphones by 20%. the headphones that stan wants to buy now cost $36. how much did the headphones cost before the price increase?

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

The edge of a cube was found to be 30 cm with a possible error in measurement of 0.4 cm. use differentials to estimate the maximum possible error, relative error, and percentage error in computing the volume of the cube and the surface area of the cube. (round your answers to four decimal places.) (a) the volume of the cube maximum possible error cm3 relative error percentage error % (b) the surface area of the cube maximum possible error cm2 relative error percentage error %

Can someone explain to me how to do