Which is the best first step when solving the following system of equations? y= 7x + 3
y= 9x
1. Multiply the first equation by 7
2. Substitute 9x for y in the first equation
3. Multiply the second equation by -3
4. Substitute 7x for y in the second equation

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 %

15. if the 8% tax on an item amounts to $0.96, what is the final price (tax included) of the item?

Afile that is 274 megabytes is being downloaded. if the download is 12.8% complete, how many megabytes have been downloaded? round your answer to the nearest tenth.