Find the surface area of a box that is 15 inches high 20 inches wide and 30 inches long. use the formula SA=2 * (lw+hw+lh). Explain how you do it.

So you multiple length times the width (lw) then multiple the height times the width (hw) and then multiply the length times the height (lh)

add all of those numbers together.

times that answer by 2.

SA=2 * ((30*20) + (15*20) + (30*15))

SA=2 * (600+300+450)

SA=2*1350

SA=2700

SA = 2 (20*30 + 20*15 + 30*15)

= 2 (600 + 300 + 450)

= 2 (1350)

= 2700