The lines represented by the equations y = -2x = 6 and 2y + x = -16 are

are ya tryin to ask something or is this a statement

it's undefined because anything multiplied by 0 is 0. that said, 7 days is 168 hours

answer: 4  

the square root of 16 is 4. it is a very simple mathematic concept. a square root when a number multiplied by itself will result in a number. here, the number 16 comes when 4 is multiplied by 4. hence the square root of 16 is 4. you can always figure out a square root by the inverse operation of squaring.